Your thoughts on possible cause of car trouble ** EDIT: Issues identified
03-31-2011, 10:08 PM
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Your thoughts on possible cause of car trouble ** EDIT: Issues identified
EDIT: See post #37 on page 3 for mechanic's diagnosis, list of problems he identified and suggested repairs.
==================================================
At the risk of sounding like a complete fool, I'd like to run by you guys a possible scenario/diagnosis to my recent car woes. So here's the background - I'll make it as brief as possible - please let me know your thoughts.
My car died the other day, I had it towed to a shop and am still waiting to hear from them. Before towing it, I tried every suggestion from the forum which I was capable of doing myself - new battery, new ground strap, fiddling with fuses and relays, etc -– but nothing worked. I’ve been freaking out about this mostly because since buying the car I haven't been able to get the flexplate checked for TBF. That's a whole other story covered in earlier threads but basically a stubborn mechanic refused to do the check because he "does not believe TBF is a real threat" and I had a really hard time finding another mechanic in the area with 928 experience. Anyway, so I've been anxiously awaiting word from the (new) mechanic, fearing the worse - meanwhile scouring the forum trying to piece together what might have gone wrong.
This afternoon I came across a thread about skid plates and it suddenly hit me - I killed my car by thrashing the alternator! I think. Not a novel theory by any means - I know - but until now it was only one among many possibilities, and not even a prominent one at that, so narrowing it down to this (if right) would mark major progress as far as I'm concerned.
So here is why I’m thinking the alternator must be the culprit. The skid plate discussion triggered my memory that about two days before my car died I slammed onto a speed bump that I literally just did not see at night. Mind you, I have no idea how I could have forgotten this incident because it was quite painful at the moment, but perhaps I was too caught up in my fear of TBF to exercise my memory and common sense.
With the speed bump incident now in mind, I tried to connect the dots with other issues the car has been having. The first being that I recently noticed the car seemed a bit more susceptible to scraping when going over bumps, sloped driveways etc. even at low speed (as if it were lower to the ground). I thought maybe bad motor mounts, shocks, etc but figured I'd get it looked at as soon as I found a new mechanic (a TBF-believer).
The car had done some other wacky stuff recently. The worst of these (which I previously posted about) was what a rennlister called "bouncing idle". Upon startup and braking the car would cycle the idle from really high, to really low - almost stalling (but never actually stalling), back to high, then back to low, etc. This went on for a few days and suddenly the problem seemed to have disappeared (sometime later it resurfaced but again only occurred 2-3 more times). Since it occurred intermittently and seemed to have gone away, I simply added it to the to-do list for the new mechanic.
Prior to this idling problem, there had been a couple of odd things I'd noticed shortly after buying the car:
-Knocking/clunking sound that always occurred shortly after startup. At first I thought it happened the first time I hit the brakes after a startup but that might just be a timing coincidence-in any case it’s definitely shortly after I start driving.
-Warning light (!) almost always on
And, just recently (days before car died), on two occasions the instrument cluster lights flickered as if they were going out (odd since I had the Jager LED kit put in shortly after buying the car).
After going over all this in my head it seemed obvious that the alternator was the likely suspect. I referred back to my previous thread on the idling problem and sure enough someone had suggested the alternator to me but since they quickly followed that with ‘or TBF’ I guess I ignored the first and focused on the more dismal suggestion (guess I’m not an optimist-lol). So I did some more searching on the symptoms I described-this time in conjunction with ‘alternator’ as a keyword-and found numerous posts linking these to alternator-related failure.
So… piecing it all together it looks like the scenario might have gone something like this:
- the alternator was already resting somewhat low when I bought the car (since the knocking sound has occurred from day one)
-it’s probably been knocked about a bit since then becoming looser each time, causing it rest lower and lower which, in turn, increased the frequency/force of each impact (which would explain why its seemed more susceptible to bumps/driveways recently)
-until the slamming on the speed bump the other night finally did it in
So what do you guys think? Does this seem like a plausible explanation? Are there any other malfunctions/failures (non-alternator related) that could account for all the same symptoms? Could the symptoms be completely unrelated?
By the way, service records show the alternator was replaced with a rebuilt unit 3.5 years and about 6k miles ago. Sorry for the lengthy post. Any feedback you might have will be very much appreciated.
==================================================
At the risk of sounding like a complete fool, I'd like to run by you guys a possible scenario/diagnosis to my recent car woes. So here's the background - I'll make it as brief as possible - please let me know your thoughts.
My car died the other day, I had it towed to a shop and am still waiting to hear from them. Before towing it, I tried every suggestion from the forum which I was capable of doing myself - new battery, new ground strap, fiddling with fuses and relays, etc -– but nothing worked. I’ve been freaking out about this mostly because since buying the car I haven't been able to get the flexplate checked for TBF. That's a whole other story covered in earlier threads but basically a stubborn mechanic refused to do the check because he "does not believe TBF is a real threat" and I had a really hard time finding another mechanic in the area with 928 experience. Anyway, so I've been anxiously awaiting word from the (new) mechanic, fearing the worse - meanwhile scouring the forum trying to piece together what might have gone wrong.
This afternoon I came across a thread about skid plates and it suddenly hit me - I killed my car by thrashing the alternator! I think. Not a novel theory by any means - I know - but until now it was only one among many possibilities, and not even a prominent one at that, so narrowing it down to this (if right) would mark major progress as far as I'm concerned.
So here is why I’m thinking the alternator must be the culprit. The skid plate discussion triggered my memory that about two days before my car died I slammed onto a speed bump that I literally just did not see at night. Mind you, I have no idea how I could have forgotten this incident because it was quite painful at the moment, but perhaps I was too caught up in my fear of TBF to exercise my memory and common sense.
With the speed bump incident now in mind, I tried to connect the dots with other issues the car has been having. The first being that I recently noticed the car seemed a bit more susceptible to scraping when going over bumps, sloped driveways etc. even at low speed (as if it were lower to the ground). I thought maybe bad motor mounts, shocks, etc but figured I'd get it looked at as soon as I found a new mechanic (a TBF-believer).
The car had done some other wacky stuff recently. The worst of these (which I previously posted about) was what a rennlister called "bouncing idle". Upon startup and braking the car would cycle the idle from really high, to really low - almost stalling (but never actually stalling), back to high, then back to low, etc. This went on for a few days and suddenly the problem seemed to have disappeared (sometime later it resurfaced but again only occurred 2-3 more times). Since it occurred intermittently and seemed to have gone away, I simply added it to the to-do list for the new mechanic.
Prior to this idling problem, there had been a couple of odd things I'd noticed shortly after buying the car:
-Knocking/clunking sound that always occurred shortly after startup. At first I thought it happened the first time I hit the brakes after a startup but that might just be a timing coincidence-in any case it’s definitely shortly after I start driving.
-Warning light (!) almost always on
And, just recently (days before car died), on two occasions the instrument cluster lights flickered as if they were going out (odd since I had the Jager LED kit put in shortly after buying the car).
After going over all this in my head it seemed obvious that the alternator was the likely suspect. I referred back to my previous thread on the idling problem and sure enough someone had suggested the alternator to me but since they quickly followed that with ‘or TBF’ I guess I ignored the first and focused on the more dismal suggestion (guess I’m not an optimist-lol). So I did some more searching on the symptoms I described-this time in conjunction with ‘alternator’ as a keyword-and found numerous posts linking these to alternator-related failure.
So… piecing it all together it looks like the scenario might have gone something like this:
- the alternator was already resting somewhat low when I bought the car (since the knocking sound has occurred from day one)
-it’s probably been knocked about a bit since then becoming looser each time, causing it rest lower and lower which, in turn, increased the frequency/force of each impact (which would explain why its seemed more susceptible to bumps/driveways recently)
-until the slamming on the speed bump the other night finally did it in
So what do you guys think? Does this seem like a plausible explanation? Are there any other malfunctions/failures (non-alternator related) that could account for all the same symptoms? Could the symptoms be completely unrelated?
By the way, service records show the alternator was replaced with a rebuilt unit 3.5 years and about 6k miles ago. Sorry for the lengthy post. Any feedback you might have will be very much appreciated.
Last edited by 88MB928; 06-10-2011 at 06:23 PM.
03-31-2011, 10:26 PM
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More information would help. You say, "Before towing it, I tried every suggestion from the forum which I was capable of doing myself - new battery, new ground strap, fiddling with fuses and relays, etc -– but nothing worked."
But "nothing worked" isn't much to go on. What did it do when you attempted to start it again? Absolutely nothing? Clicking, but not turning over? Something else?
But "nothing worked" isn't much to go on. What did it do when you attempted to start it again? Absolutely nothing? Clicking, but not turning over? Something else?
03-31-2011, 10:33 PM
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At the risk of sounding like a complete fool, I'd like to run by you guys a possible scenario/diagnosis to my recent car woes. So here's the background - I'll make it as brief as possible - please let me know your thoughts.
My car died the other day, I had it towed to a shop and am still waiting to hear from them. Before towing it, I tried every suggestion from the forum which I was capable of doing myself - new battery, new ground strap, fiddling with fuses and relays, etc -– but nothing worked. I’ve been freaking out about this mostly because since buying the car I haven't been able to get the flexplate checked for TBF. That's a whole other story covered in earlier threads but basically a stubborn mechanic refused to do the check because he "does not believe TBF is a real threat" and I had a really hard time finding another mechanic in the area with 928 experience. Anyway, so I've been anxiously awaiting word from the (new) mechanic, fearing the worse - meanwhile scouring the forum trying to piece together what might have gone wrong.
This afternoon I came across a thread about skid plates and it suddenly hit me - I killed my car by thrashing the alternator! I think. Not a novel theory by any means - I know - but until now it was only one among many possibilities, and not even a prominent one at that, so narrowing it down to this (if right) would mark major progress as far as I'm concerned.
So here is why I’m thinking the alternator must be the culprit. The skid plate discussion triggered my memory that about two days before my car died I slammed onto a speed bump that I literally just did not see at night. Mind you, I have no idea how I could have forgotten this incident because it was quite painful at the moment, but perhaps I was too caught up in my fear of TBF to exercise my memory and common sense.
With the speed bump incident now in mind, I tried to connect the dots with other issues the car has been having. The first being that I recently noticed the car seemed a bit more susceptible to scraping when going over bumps, sloped driveways etc. even at low speed (as if it were lower to the ground). I thought maybe bad motor mounts, shocks, etc but figured I'd get it looked at as soon as I found a new mechanic (a TBF-believer).
The car had done some other wacky stuff recently. The worst of these (which I previously posted about) was what a rennlister called "bouncing idle". Upon startup and braking the car would cycle the idle from really high, to really low - almost stalling (but never actually stalling), back to high, then back to low, etc. This went on for a few days and suddenly the problem seemed to have disappeared (sometime later it resurfaced but again only occurred 2-3 more times). Since it occurred intermittently and seemed to have gone away, I simply added it to the to-do list for the new mechanic.
Prior to this idling problem, there had been a couple of odd things I'd noticed shortly after buying the car:
-Knocking/clunking sound that always occurred shortly after startup. At first I thought it happened the first time I hit the brakes after a startup but that might just be a timing coincidence-in any case it’s definitely shortly after I start driving.
-Warning light (!) almost always on
And, just recently (days before car died), on two occasions the instrument cluster lights flickered as if they were going out (odd since I had the Jager LED kit put in shortly after buying the car).
After going over all this in my head it seemed obvious that the alternator was the likely suspect. I referred back to my previous thread on the idling problem and sure enough someone had suggested the alternator to me but since they quickly followed that with ‘or TBF’ I guess I ignored the first and focused on the more dismal suggestion (guess I’m not an optimist-lol). So I did some more searching on the symptoms I described-this time in conjunction with ‘alternator’ as a keyword-and found numerous posts linking these to alternator-related failure.
So… piecing it all together it looks like the scenario might have gone something like this:
- the alternator was already resting somewhat low when I bought the car (since the knocking sound has occurred from day one)
-it’s probably been knocked about a bit since then becoming looser each time, causing it rest lower and lower which, in turn, increased the frequency/force of each impact (which would explain why its seemed more susceptible to bumps/driveways recently)
-until the slamming on the speed bump the other night finally did it in
So what do you guys think? Does this seem like a plausible explanation? Are there any other malfunctions/failures (non-alternator related) that could account for all the same symptoms? Could the symptoms be completely unrelated?
By the way, service records show the alternator was replaced with a rebuilt unit 3.5 years and about 6k miles ago. Sorry for the lengthy post. Any feedback you might have will be very much appreciated.
My car died the other day, I had it towed to a shop and am still waiting to hear from them. Before towing it, I tried every suggestion from the forum which I was capable of doing myself - new battery, new ground strap, fiddling with fuses and relays, etc -– but nothing worked. I’ve been freaking out about this mostly because since buying the car I haven't been able to get the flexplate checked for TBF. That's a whole other story covered in earlier threads but basically a stubborn mechanic refused to do the check because he "does not believe TBF is a real threat" and I had a really hard time finding another mechanic in the area with 928 experience. Anyway, so I've been anxiously awaiting word from the (new) mechanic, fearing the worse - meanwhile scouring the forum trying to piece together what might have gone wrong.
This afternoon I came across a thread about skid plates and it suddenly hit me - I killed my car by thrashing the alternator! I think. Not a novel theory by any means - I know - but until now it was only one among many possibilities, and not even a prominent one at that, so narrowing it down to this (if right) would mark major progress as far as I'm concerned.
So here is why I’m thinking the alternator must be the culprit. The skid plate discussion triggered my memory that about two days before my car died I slammed onto a speed bump that I literally just did not see at night. Mind you, I have no idea how I could have forgotten this incident because it was quite painful at the moment, but perhaps I was too caught up in my fear of TBF to exercise my memory and common sense.
With the speed bump incident now in mind, I tried to connect the dots with other issues the car has been having. The first being that I recently noticed the car seemed a bit more susceptible to scraping when going over bumps, sloped driveways etc. even at low speed (as if it were lower to the ground). I thought maybe bad motor mounts, shocks, etc but figured I'd get it looked at as soon as I found a new mechanic (a TBF-believer).
The car had done some other wacky stuff recently. The worst of these (which I previously posted about) was what a rennlister called "bouncing idle". Upon startup and braking the car would cycle the idle from really high, to really low - almost stalling (but never actually stalling), back to high, then back to low, etc. This went on for a few days and suddenly the problem seemed to have disappeared (sometime later it resurfaced but again only occurred 2-3 more times). Since it occurred intermittently and seemed to have gone away, I simply added it to the to-do list for the new mechanic.
Prior to this idling problem, there had been a couple of odd things I'd noticed shortly after buying the car:
-Knocking/clunking sound that always occurred shortly after startup. At first I thought it happened the first time I hit the brakes after a startup but that might just be a timing coincidence-in any case it’s definitely shortly after I start driving.
-Warning light (!) almost always on
And, just recently (days before car died), on two occasions the instrument cluster lights flickered as if they were going out (odd since I had the Jager LED kit put in shortly after buying the car).
After going over all this in my head it seemed obvious that the alternator was the likely suspect. I referred back to my previous thread on the idling problem and sure enough someone had suggested the alternator to me but since they quickly followed that with ‘or TBF’ I guess I ignored the first and focused on the more dismal suggestion (guess I’m not an optimist-lol). So I did some more searching on the symptoms I described-this time in conjunction with ‘alternator’ as a keyword-and found numerous posts linking these to alternator-related failure.
So… piecing it all together it looks like the scenario might have gone something like this:
- the alternator was already resting somewhat low when I bought the car (since the knocking sound has occurred from day one)
-it’s probably been knocked about a bit since then becoming looser each time, causing it rest lower and lower which, in turn, increased the frequency/force of each impact (which would explain why its seemed more susceptible to bumps/driveways recently)
-until the slamming on the speed bump the other night finally did it in
So what do you guys think? Does this seem like a plausible explanation? Are there any other malfunctions/failures (non-alternator related) that could account for all the same symptoms? Could the symptoms be completely unrelated?
By the way, service records show the alternator was replaced with a rebuilt unit 3.5 years and about 6k miles ago. Sorry for the lengthy post. Any feedback you might have will be very much appreciated.
- -My car died the other day
- -about two days before my car died I slammed onto a speed bump
- -Upon startup and braking the car would cycle the idle from really high, to really low - almost stalling (but never actually stalling), back to high, then back to low, etc. This went on for a few days and suddenly the problem seemed to have disappeared (sometime later it resurfaced but again only occurred 2-3 more times)
- --Knocking/clunking sound that always occurred shortly after startup
- --Warning light (!) almost always on
- -on two occasions the instrument cluster lights flickered as if they were going out
I would say 1,2,5 and 6, and possibly 4, are related to your speed bump encounter. and possibly, prior condition of your alternator mounting. But since I can't account for 3, I may be missing something important, which I am sure others here can figure out. I did the extraction as an exercise just to get my own thoughts in order, no criticism of your narrative intended. Good luck with this, and get rid of that mechanic.
Last edited by M. Requin; 03-31-2011 at 10:35 PM. Reason: sp
03-31-2011, 10:34 PM
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It is possible that could be the cause, never seen that exactly, but I have not seen as many 928's as others here, but have seen a few.
Seems if it was a bad alternator a fresh battery would cure that problem for at least 20-30 minutes.
The idle hunting or surge can be a difficult problem to track down on a 928 at times, and I doubt that the alternator is the root cause of surge/hunt.
When you say it will not start, exactly what do you mean?
Does it turn over at normal speed and just not run?
Does it spin over slowly and not start?
Does it spin over fast and not start?
The alternator issue is a fairly easy one to diagnosis, but any mechanic that says thrust bearing failure is not a issue with these cars is a freaking lair, cause he does not know 928's.
Seems if it was a bad alternator a fresh battery would cure that problem for at least 20-30 minutes.
The idle hunting or surge can be a difficult problem to track down on a 928 at times, and I doubt that the alternator is the root cause of surge/hunt.
When you say it will not start, exactly what do you mean?
Does it turn over at normal speed and just not run?
Does it spin over slowly and not start?
Does it spin over fast and not start?
The alternator issue is a fairly easy one to diagnosis, but any mechanic that says thrust bearing failure is not a issue with these cars is a freaking lair, cause he does not know 928's.
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03-31-2011, 10:48 PM
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BTW, since you're obviously concerned about TBF (understandable, since one probably should worry about this a little, or — better stated — take measures to prevent it) and you're wisely going to make sure that crank end play is measured, you might as well spend $85 and get a PKlamp (see also Bill Ball's "My PKlamp Experience" thread) and have it put on (5 to 10 minute job once you're in there anyway) at the same time the crank end play measurement (and flexplate bow check etc.) is taken. A little extra defense against TBF. (SuperClamp would be even better, but that's a big job).
03-31-2011, 10:54 PM
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I think you have multiple problems, most likly unrelated.
1. If you hit the alternator with the speed bump it usually destroys it immediatly and the car would die as soon as the battery went down. Also you would get multiple lights in the instrument panel. Lastly there is no way for the alternator to drop lower and lower with each hit. The belt would support it and it also has three other mount points.
1a. I suspect your suspension has setteled and needs to be raised. The factory settings are best. Lower looks cool but it effects the handling in a negative way.
2. The idle surging is almost always caused by the idle stabilizer failing due to an oil/gunk build up. You can try spraying WD-40 into the vacuum hose that leads to the stabilizer, but this is usually a temporary fix. The perment fix is to remove the intake manifold and throughly clean or replace the valve.
3. -Knocking/clunking sound that always occurred shortly after startup. Need more info . . .could be the transmission, a loose suspension component, loose brake caliper etc. Does it clunk more than once with start up, or does it go away after driving for awhile, does it sound like it's coming from the front or rear, do you feel it in the steering wheel or in the pedals? Do you feel it in your butt?
4. Warning light (!) almost always on. Is usually an electrical problem. Is it associated with any other dash lights? Is everything else normal; oil pressure, water temperture, voltmeter reading approx. 13.5 volts when running. Are all of your dash warning lights working? Turn the ignition switch to the run position without starting the car. Voltmeter should read 12 volts and all warning lights should come on. They all should go out when the car is started.
Lastly, TBF is very real. Do a search on the limits and find a mechanic who will do the check even if he/she doesn't believe it's real. Usually with TBF the car will get harder and harder to accelerate when it warms up, will be difficult to impossible to re-start when warm/hot and means the death of your engine.
Let us know what the mechanic finds.
1. If you hit the alternator with the speed bump it usually destroys it immediatly and the car would die as soon as the battery went down. Also you would get multiple lights in the instrument panel. Lastly there is no way for the alternator to drop lower and lower with each hit. The belt would support it and it also has three other mount points.
1a. I suspect your suspension has setteled and needs to be raised. The factory settings are best. Lower looks cool but it effects the handling in a negative way.
2. The idle surging is almost always caused by the idle stabilizer failing due to an oil/gunk build up. You can try spraying WD-40 into the vacuum hose that leads to the stabilizer, but this is usually a temporary fix. The perment fix is to remove the intake manifold and throughly clean or replace the valve.
3. -Knocking/clunking sound that always occurred shortly after startup. Need more info . . .could be the transmission, a loose suspension component, loose brake caliper etc. Does it clunk more than once with start up, or does it go away after driving for awhile, does it sound like it's coming from the front or rear, do you feel it in the steering wheel or in the pedals? Do you feel it in your butt?
4. Warning light (!) almost always on. Is usually an electrical problem. Is it associated with any other dash lights? Is everything else normal; oil pressure, water temperture, voltmeter reading approx. 13.5 volts when running. Are all of your dash warning lights working? Turn the ignition switch to the run position without starting the car. Voltmeter should read 12 volts and all warning lights should come on. They all should go out when the car is started.
Lastly, TBF is very real. Do a search on the limits and find a mechanic who will do the check even if he/she doesn't believe it's real. Usually with TBF the car will get harder and harder to accelerate when it warms up, will be difficult to impossible to re-start when warm/hot and means the death of your engine.
Let us know what the mechanic finds.
03-31-2011, 11:14 PM
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For sure I will agree on that.
Yep
We must get the strange ones, but then again by the time they get to me, many parts have usually been replaced.
Just look at the chit I went through on my own 928.
Good questions.
Yep
TBF is very real and for many cars it is a death sentence.
1. If you hit the alternator with the speed bump it usually destroys it immediatly and the car would die as soon as the battery went down. Also you would get multiple lights in the instrument panel. Lastly there is no way for the alternator to drop lower and lower with each hit. The belt would support it and it also has three other mount points.
1a. I suspect your suspension has setteled and needs to be raised. The factory settings are best. Lower looks cool but it effects the handling in a negative way.
1a. I suspect your suspension has setteled and needs to be raised. The factory settings are best. Lower looks cool but it effects the handling in a negative way.
2. The idle surging is almost always caused by the idle stabilizer failing due to an oil/gunk build up. You can try spraying WD-40 into the vacuum hose that leads to the stabilizer, but this is usually a temporary fix. The perment fix is to remove the intake manifold and throughly clean or replace the valve.
Just look at the chit I went through on my own 928.
3. -Knocking/clunking sound that always occurred shortly after startup. Need more info . . .could be the transmission, a loose suspension component, loose brake caliper etc. Does it clunk more than once with start up, or does it go away after driving for awhile, does it sound like it's coming from the front or rear, do you feel it in the steering wheel or in the pedals? Do you feel it in your butt?
4. Warning light (!) almost always on. Is usually an electrical problem. Is it associated with any other dash lights? Is everything else normal; oil pressure, water temperture, voltmeter reading approx. 13.5 volts when running. Are all of your dash warning lights working? Turn the ignition switch to the run position without starting the car. Voltmeter should read 12 volts and all warning lights should come on. They all should go out when the car is started.
Lastly, TBF is very real. Do a search on the limits and find a mechanic who will do the check even if he/she doesn't believe it's real. Usually with TBF the car will get harder and harder to accelerate when it warms up, will be difficult to impossible to re-start when warm/hot and means the death of your engine.
Let us know what the mechanic finds.
Let us know what the mechanic finds.
04-01-2011, 12:11 AM
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I always expect that there will be one cause creating three symptoms, but in the end it seems more like each symptom has three causes. And, sometimes the problems that make the car run just a little off can be quite difficult to find, even if there is only one cause. Unless you really have a lot of time to dig in and learn and solve and be frustrated, your salvation is likely a good mechanic. Hopefully your new one will work out. If not, my suggestion would be to start a new thread titled "anybody know a 928 savvy mechanic in Miami?". Seems like there should be one.
04-01-2011, 01:14 AM
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I would say 1,2,5 and 6, and possibly 4, are related to your speed bump encounter. and possibly, prior condition of your alternator mounting [...] I did the extraction as an exercise just to get my own thoughts in order, no criticism of your narrative intended. Good luck with this, and get rid of that mechanic.
blown 87, the fresh battery made no discernible difference - the car responded the same way with the old and new batteries. from the no-start descriptions you listed I would say the closest is "spun slowly but didn't start"
04-01-2011, 01:55 AM
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Hi Jim, thanks for your input. I'll try my best to answer all your questions.
This seems completely intuitive-the fact that the car would die over a day later does throw me off (that's probably why I didn't even think to consider the relevance of the speed bump at first).
I am not familiar with the alternator system at all but your description definitely suggests that my theory is way off.
This would make sense since I recall PO mentioning that the next major work he anticipated the car would need was the suspension-IIRC he thought it was still the original stock setup. And I have zero interest in lowering my car so that's no issue for me.
The car is already in the shop but I will discuss this with the mechanic.
Only clunks once and goes away. Sounds like its coming from rear. Never noticed any impact on steering wheel, pedals, or my butt (lol)
Not associated with any other lights. Only dash light not working last I checked was the 'D' n the PRND. Warning lights were coming on when ignition in run and going off upon starting.
I have read how real TBF is which is why I started looking for a new mechanic the moment he said that. Luckily, I have not experienced the symptoms you describe so I'm hopeful its something other than TBF.
I will definitely keep you guys posted. Thanks again for your help
1. If you hit the alternator with the speed bump it usually destroys it immediatly and the car would die as soon as the battery went down. Also you would get multiple lights in the instrument panel. Lastly there is no way for the alternator to drop lower and lower with each hit. The belt would support it and it also has three other mount points.
I am not familiar with the alternator system at all but your description definitely suggests that my theory is way off.
2. The idle surging is almost always caused by the idle stabilizer failing due to an oil/gunk build up. You can try spraying WD-40 into the vacuum hose that leads to the stabilizer, but this is usually a temporary fix. The perment fix is to remove the intake manifold and throughly clean or replace the valve.
3. -Knocking/clunking sound that always occurred shortly after startup. Need more info . . .Does it clunk more than once with start up, or does it go away after driving for awhile, does it sound like it's coming from the front or rear, do you feel it in the steering wheel or in the pedals? Do you feel it in your butt?
4. Warning light (!) almost always on. Is usually an electrical problem. Is it associated with any other dash lights? Is everything else normal; oil pressure, water temperture, voltmeter reading approx. 13.5 volts when running. Are all of your dash warning lights working? Turn the ignition switch to the run position without starting the car. Voltmeter should read 12 volts and all warning lights should come on. They all should go out when the car is started.
Lastly, TBF is very real. Do a search on the limits and find a mechanic who will do the check even if he/she doesn't believe it's real. Usually with TBF the car will get harder and harder to accelerate when it warms up, will be difficult to impossible to re-start when warm/hot and means the death of your engine.
I will definitely keep you guys posted. Thanks again for your help