944 troubleshooting needed
02-28-2007, 02:19 PM
#1
Nordschleife Master
Thread Starter
944 troubleshooting needed
As for my 944 - Porsche said I'd put the wrong plugs in (I don't think it made a difference, but did put back in OEM sparkplugs, rather than the Platinum points. And after she was towed, she did work, ran well for a day or two, and right on schedule, began not firing on all cylinders, and now can't maintain running. She did idle fine for 3 hours even, and I drove her for errands.
I've been trying to go backwards, and deduce what could've possibly gone wrong with her. She was fine, until she blew the waterpump. Something went horribly wrong, after the waterpump was replaced; but WHAT!? What on earth could seemingly repair itself when the car is towed, then do this over and over again!?
I'm tired of feeling like I'm throwing money at a Phantom; even one of the Porsche facilities couldn't find the problem, because she ran fine after she was towed!
I can repair her, if I can find the issue. I can't troubleshoot the electrical, because that is the part corrupted on my CDs!
She will start - but sounds like she's not running on all cylinders; you want to give her gas to keep her running, which will eventually flood her, and stop her.
She will restart, but just can't be driven further than the driveway. The DME was replaced, but was overheating; Porsche said the Platinum plugs may have been 'overclocking' it, and claimed that many cars that were not turbo had this issue, until going back to the non-platinum plugs.
What has been replaced:
Fuel Pressure Regulator
Waterpump
Distributor Cap
Rotor
DME
Spark plugs (again)
Something that was also added, that has had me wondering:
Car stereo; older Sony or Pioneer cassette (have Ipod, no need for CDs). Wondering if the wire that was taped up is shorting things out? There is also a big black one hanging down from under the dash, of which I taped up, and no one thinks is any big deal. Guess both of these wires must have gone to the old stereo (that drove 4 speakers and 2 subwoofers - they are still under the passenger seats [I think that's what they are]) or to the old Clifford Alarm system.
There was ONE mechanic at Porsche that had an idea what was going wrong, but he had an injury that put him back out of work the next day. Those who worked on her, never heard my conversation with him. Let's just say - the owners got an earful, upon presentation of the bill, that didn't repair my car! Good owners do listen to the customers, and are reasonable.
- Julie
I've been trying to go backwards, and deduce what could've possibly gone wrong with her. She was fine, until she blew the waterpump. Something went horribly wrong, after the waterpump was replaced; but WHAT!? What on earth could seemingly repair itself when the car is towed, then do this over and over again!?
I'm tired of feeling like I'm throwing money at a Phantom; even one of the Porsche facilities couldn't find the problem, because she ran fine after she was towed!
I can repair her, if I can find the issue. I can't troubleshoot the electrical, because that is the part corrupted on my CDs!
She will start - but sounds like she's not running on all cylinders; you want to give her gas to keep her running, which will eventually flood her, and stop her.
She will restart, but just can't be driven further than the driveway. The DME was replaced, but was overheating; Porsche said the Platinum plugs may have been 'overclocking' it, and claimed that many cars that were not turbo had this issue, until going back to the non-platinum plugs.
What has been replaced:
Fuel Pressure Regulator
Waterpump
Distributor Cap
Rotor
DME
Spark plugs (again)
Something that was also added, that has had me wondering:
Car stereo; older Sony or Pioneer cassette (have Ipod, no need for CDs). Wondering if the wire that was taped up is shorting things out? There is also a big black one hanging down from under the dash, of which I taped up, and no one thinks is any big deal. Guess both of these wires must have gone to the old stereo (that drove 4 speakers and 2 subwoofers - they are still under the passenger seats [I think that's what they are]) or to the old Clifford Alarm system.
There was ONE mechanic at Porsche that had an idea what was going wrong, but he had an injury that put him back out of work the next day. Those who worked on her, never heard my conversation with him. Let's just say - the owners got an earful, upon presentation of the bill, that didn't repair my car! Good owners do listen to the customers, and are reasonable.
- Julie
Last edited by Devia; 03-02-2007 at 02:29 PM.
02-28-2007, 02:38 PM
#2
Race Director
Originally Posted by Devia
There was ONE mechanic at Porsche that had an idea what was going wrong, but he had an injury that put him back out of work the next day. Those who worked on her, never heard my conversation with him.
02-28-2007, 02:48 PM
#3
Addict
Rennlist Member
Rennlist Member
Join Date: Apr 2002
Location: St. Louis
Posts: 1,176
Likes: 0
Received 0 Likes
on
0 Posts
2 ideas. Changing the waterpump and plugs makes you have to move the spark plug wires around. If they are older, this moving around may break the wires internally or at the ends causing them to fire radomly. Also I had some spark plugs that I flooded out a couple of times because of injector problems and even though they were brand new bosch non-platinum, they still stopped working after they were flooded. Even after drying them back out thoroughly they never worked again.
02-28-2007, 03:18 PM
#4
Nordschleife Master
Thread Starter
Replacing the sparkplug wires did occur to me, over the past few days. I had planned to be there, when the waterpump was being replaced - but the guys did it to be nice! Ergo, yes; it's something I was thinking of, so I'll order a set today.
The mechanic never said what was wrong with the car, as he said the plugs had to be changed out first - so, I picked up a set of Bosch OEMs (noo way was I paying their price of $35 each plug, plus $270 to stick them in!).
I did check them, and they didn't appear to be wet; but, I'll keep what you said in mind.
Thanks!
- Julie
The mechanic never said what was wrong with the car, as he said the plugs had to be changed out first - so, I picked up a set of Bosch OEMs (noo way was I paying their price of $35 each plug, plus $270 to stick them in!).
I did check them, and they didn't appear to be wet; but, I'll keep what you said in mind.
Thanks!
- Julie
02-28-2007, 03:36 PM
#5
Nordschleife Master
Defenetley change the plug wires if you dont know the history on them. When its really dark out later tonight start the car up and look at the wires, they might be bad enough that you can see them arcing.
When the car blew the water pump did it over heat? Do you have an over pressurized cooling system, mysterious loss of coolant? Strange readings on the temp gauge? Just throwing it out there, but could be a blown headgasket. Your car will face symptoms of misfiring on startups until all the coolant is burned off in the cylinder. It could be a minor leak, there does not need to be mixing of oil and coolant. Coolant could be seeping into the cylinder when the engine is hot, if you depressurize the cooling system before letting it sit, coolant will not leak past into the cylinders. My car did this and was completely normal, only misfiring if i ran the car up to normal temp, then shut if off and waited an hour or so. If i ran it up to temp, then depressurized the cooling system before letting it sit, it started fine. If the car misfires on startups, turn if off immediately and take each plug out and look into the cylinder with a flash light, you may see coolant pooling on top of the cylinder.
When the car blew the water pump did it over heat? Do you have an over pressurized cooling system, mysterious loss of coolant? Strange readings on the temp gauge? Just throwing it out there, but could be a blown headgasket. Your car will face symptoms of misfiring on startups until all the coolant is burned off in the cylinder. It could be a minor leak, there does not need to be mixing of oil and coolant. Coolant could be seeping into the cylinder when the engine is hot, if you depressurize the cooling system before letting it sit, coolant will not leak past into the cylinders. My car did this and was completely normal, only misfiring if i ran the car up to normal temp, then shut if off and waited an hour or so. If i ran it up to temp, then depressurized the cooling system before letting it sit, it started fine. If the car misfires on startups, turn if off immediately and take each plug out and look into the cylinder with a flash light, you may see coolant pooling on top of the cylinder.
02-28-2007, 05:00 PM
#6
Racer
Join Date: Jul 2006
Location: Los Angeles, CA
Posts: 389
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by Techno Duck
Defenetley change the plug wires if you dont know the history on them. When its really dark out later tonight start the car up and look at the wires, they might be bad enough that you can see them arcing.
When the car blew the water pump did it over heat? Do you have an over pressurized cooling system, mysterious loss of coolant? Strange readings on the temp gauge? Just throwing it out there, but could be a blown headgasket. Your car will face symptoms of misfiring on startups until all the coolant is burned off in the cylinder. It could be a minor leak, there does not need to be mixing of oil and coolant. Coolant could be seeping into the cylinder when the engine is hot, if you depressurize the cooling system before letting it sit, coolant will not leak past into the cylinders. My car did this and was completely normal, only misfiring if i ran the car up to normal temp, then shut if off and waited an hour or so. If i ran it up to temp, then depressurized the cooling system before letting it sit, it started fine. If the car misfires on startups, turn if off immediately and take each plug out and look into the cylinder with a flash light, you may see coolant pooling on top of the cylinder.
When the car blew the water pump did it over heat? Do you have an over pressurized cooling system, mysterious loss of coolant? Strange readings on the temp gauge? Just throwing it out there, but could be a blown headgasket. Your car will face symptoms of misfiring on startups until all the coolant is burned off in the cylinder. It could be a minor leak, there does not need to be mixing of oil and coolant. Coolant could be seeping into the cylinder when the engine is hot, if you depressurize the cooling system before letting it sit, coolant will not leak past into the cylinders. My car did this and was completely normal, only misfiring if i ran the car up to normal temp, then shut if off and waited an hour or so. If i ran it up to temp, then depressurized the cooling system before letting it sit, it started fine. If the car misfires on startups, turn if off immediately and take each plug out and look into the cylinder with a flash light, you may see coolant pooling on top of the cylinder.
-.- Tell me more.
My NA had been having small missing on cold starts, weird oil temps, then blew the headgasket.
Resurfaced head, replaced gasket.
Oil temps seem to be normal, although pressure is normally 3 but drops to 2 a in heavy traffic (yet is still 35 degrees out).
Still get small missing of cylinders on cold starts.
Am I screwed again?
02-28-2007, 05:00 PM
#7
Nordschleife Master
Thread Starter
I'd just replaced the Fuel Pressure regulator, and had said, "Hey, let's see if I can break it!" gunned
it, and then this horrible noise came out from under the hood, and I was just a few blocks from the house. She never overheated, never fear! That's what AAA is for, so you don't break your car worse.
She doesn't run fine at all, after she runs great for a day or two. I've checked the oil & the antifreeze, as have numerous others, and she still is strong in that department (though I've wanted to replace it, just because I'm a worry wart). She's dumped me on a freeway, in the middle of an intersection. And about the freeway exit - an hour later, thought it was okay, then simply stopped running, and had to push her out of the street, into a Ford dealership, *gasp*, where they tried to sell me a new car, whilst I waited on a tow truck, lol.
What we HAVE found pooling on the cylinders: FUEL.
I'm talking with a female Porsche mechanic today, and she urged me to go through her checklist,
before dumping more money into it.
One thing, though, does bug me, is this big metal box that says, "Bosch Python Ignition", and then
says to test and analyze. Hmmm, sounds like what I'd asked the good Porsche mechanic to do,
before he went back out on Disability, for his injured shoulder.
If I'm not mistaken, that piece of equipment is the DME control unit!? Could that be an evil beastie,
causing me such wierd problems? I haven't been able to find anything on it, so I'd appreciate
everyone's response, who's ever had issues with one!
- Julie
it, and then this horrible noise came out from under the hood, and I was just a few blocks from the house. She never overheated, never fear! That's what AAA is for, so you don't break your car worse.
She doesn't run fine at all, after she runs great for a day or two. I've checked the oil & the antifreeze, as have numerous others, and she still is strong in that department (though I've wanted to replace it, just because I'm a worry wart). She's dumped me on a freeway, in the middle of an intersection. And about the freeway exit - an hour later, thought it was okay, then simply stopped running, and had to push her out of the street, into a Ford dealership, *gasp*, where they tried to sell me a new car, whilst I waited on a tow truck, lol.
What we HAVE found pooling on the cylinders: FUEL.
I'm talking with a female Porsche mechanic today, and she urged me to go through her checklist,
before dumping more money into it.
One thing, though, does bug me, is this big metal box that says, "Bosch Python Ignition", and then
says to test and analyze. Hmmm, sounds like what I'd asked the good Porsche mechanic to do,
before he went back out on Disability, for his injured shoulder.
If I'm not mistaken, that piece of equipment is the DME control unit!? Could that be an evil beastie,
causing me such wierd problems? I haven't been able to find anything on it, so I'd appreciate
everyone's response, who's ever had issues with one!
- Julie
Trending Topics
02-28-2007, 05:52 PM
#10
Not having the afm plugged in will not keep it from starting, but will keep it from running.
Use the factory diagnostic, in the workshop manual. Works every time. Lots better than guessing.
Use the factory diagnostic, in the workshop manual. Works every time. Lots better than guessing.
02-28-2007, 06:06 PM
#11
Official Bay Area Patriot
Fuse 24 Assassin
Rennlist Member
Fuse 24 Assassin
Rennlist Member
If you have fuel pooling in the cylinders, there is definitely little to no spark. I'd go for wires first. Check the ignition coil if it still runs the same. BE SURE TO GET NEW SPARK PLUGS just in case.
What is a Bosch Python? From what it sounds like, this is a different ignition or DME they are running on your car?!?! BIG NO NO. I am probably mis-interpreting this.
Pozican: No you aren't screwed. My car has a rebuilt engine and has a small miss on start up once in a while. Unless you failed following the torquing procedures for the cylinder head, that might cause coolant leaking back into the cylinders. My cooling system is not pressurizing anymore and compression is stronger than ever. Check your wires, you could be arcing. Every now and then I have to go in there and fix mine since I have 8mm wires from Lindsey Racing, which don't fit in the factory separators anymore
What is a Bosch Python? From what it sounds like, this is a different ignition or DME they are running on your car?!?! BIG NO NO. I am probably mis-interpreting this.
Pozican: No you aren't screwed. My car has a rebuilt engine and has a small miss on start up once in a while. Unless you failed following the torquing procedures for the cylinder head, that might cause coolant leaking back into the cylinders. My cooling system is not pressurizing anymore and compression is stronger than ever. Check your wires, you could be arcing. Every now and then I have to go in there and fix mine since I have 8mm wires from Lindsey Racing, which don't fit in the factory separators anymore
Last edited by TheStig; 02-28-2007 at 06:32 PM.
02-28-2007, 10:00 PM
#12
Rennlist Member
I would check to see if your ignition coil output is adequate enough: http://www.clarks-garage.com/shop-manual/ign-04.htm
Also, I was having a problem where the car would stumble, die, and not restart and I woud stick a lut macth down in the spark plug holes to burn out the excess fuel in the cylinders. I had to gap down the plugs to ~.015 to get it to run enough to drive it home (~20miles). My problem was crusty broken insulation on the spark plug wires and were arching. Magnecor makes fanastic wires for less than a $100.
Also check to see if the DME you replaced your original one with has the FQS (fuel quality switch) moved? It should be on "0". This swicth has the authority to change fuel settings from -3% -> +3% and IIRC -6% -> +6% to accomodate differing grades of fuel.
Also, I was having a problem where the car would stumble, die, and not restart and I woud stick a lut macth down in the spark plug holes to burn out the excess fuel in the cylinders. I had to gap down the plugs to ~.015 to get it to run enough to drive it home (~20miles). My problem was crusty broken insulation on the spark plug wires and were arching. Magnecor makes fanastic wires for less than a $100.
Also check to see if the DME you replaced your original one with has the FQS (fuel quality switch) moved? It should be on "0". This swicth has the authority to change fuel settings from -3% -> +3% and IIRC -6% -> +6% to accomodate differing grades of fuel.
02-28-2007, 10:14 PM
#13
im the last guy that should be giving advice around here, but you mentioned you replaced the Fuel Regulator, possibly consider changing the Fuel DAMPER as well? i know both of those units can lead to problems that sometimes make for suspect DMEs... but thats just what i read from clarks garage. figured id throw that out there.
03-01-2007, 03:52 AM
#14
Nordschleife Master
Thread Starter
Concerning the Fuel Dampener - was concerned it was gone again, but unlike before, it isn't sucking fuel into the vacuum system, so it appears to be okay. Not any other way to really check it, except last time it spat fuel across Legoland951s shoulder, when I cranked her, lol. Thought about doing it again, but didn't wish to make a potential fire hazard worse!
Well, I only replaced the DME Relay - not the board. Ergo, I'm wondering if something is wrong.
How do I check out that part, to see if things are connected properly? I have no info in my stupid
Haynes manual - checked, unless it's under something oddball.
The Bosche Python appears to have Porsche numbers on it (such as 944, etc.). Makes me wonder if they weren't just having fun with names?
I'm missing the Electrical section in my Shop manual, as it's somehow corrupted - thus, really giving me an uber headache with the car.
As for the coil, we yanked it at my cousin's house, and put a Jetta one in it, down at my cousin's house in SD. It ran fine. She ran fine for 2 months, being started up every few days and driven about. Then, I drove her home. And she promptly died 48 hours later! And that is her pattern -
drive her normally, after being tinkered with uselessly, and then she dies suddenly often times.
I didn't even know she'd stopped running in the intersection, or when I was on the freeway, because the car didn't jump or anything! Just quietly turned itself off.
WHY would it keep doing that to me, that is part of the question. I mistakenly thought McKenna Porsche, with their highly praised 944 specialist from Germany, would run a proper Diagnosis (I had serious reservations taking it there. But, they didn't do anything it appears, other than change out the sparkplugs and run her for 3 hours, and claim she was repaired - which I pointed out to the Service Manager that the issues I'd brought the car in for, is NOT what they addressed properly! And they agreed. That Service Manager, when I obtain my Cayman, shan't touch her.
Cayman, or other Porsches = positive thought.
- Julie
Well, I only replaced the DME Relay - not the board. Ergo, I'm wondering if something is wrong.
How do I check out that part, to see if things are connected properly? I have no info in my stupid
Haynes manual - checked, unless it's under something oddball.
The Bosche Python appears to have Porsche numbers on it (such as 944, etc.). Makes me wonder if they weren't just having fun with names?
I'm missing the Electrical section in my Shop manual, as it's somehow corrupted - thus, really giving me an uber headache with the car.
As for the coil, we yanked it at my cousin's house, and put a Jetta one in it, down at my cousin's house in SD. It ran fine. She ran fine for 2 months, being started up every few days and driven about. Then, I drove her home. And she promptly died 48 hours later! And that is her pattern -
drive her normally, after being tinkered with uselessly, and then she dies suddenly often times.
I didn't even know she'd stopped running in the intersection, or when I was on the freeway, because the car didn't jump or anything! Just quietly turned itself off.
WHY would it keep doing that to me, that is part of the question. I mistakenly thought McKenna Porsche, with their highly praised 944 specialist from Germany, would run a proper Diagnosis (I had serious reservations taking it there. But, they didn't do anything it appears, other than change out the sparkplugs and run her for 3 hours, and claim she was repaired - which I pointed out to the Service Manager that the issues I'd brought the car in for, is NOT what they addressed properly! And they agreed. That Service Manager, when I obtain my Cayman, shan't touch her.
Cayman, or other Porsches = positive thought.
- Julie
