Help Please 1989 S4 stops running like it got hot, but temp is good
09-21-2012, 07:07 PM
#62
Burning Brakes
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If it was a spark issue, I do not believe I could get it to fire up like she does... As time progresses, I am able to go fewer miles until I let her sit for 30 min or so. The old relay I replaced did not give me as much time as this one, but I wonder how much I have worked this one over with 200 miles...
I will probably replace it when I do the pump just for good measure... If the other pump does not fix this issue (and I want to swap it anyhow... Tired of the 044 whine I get), then I will try to check for spark, but I have so little time that it does not run, I am not sure I could prove that one way or the other...
09-21-2012, 10:03 PM
#63
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Yes, I would swap in a stock pump for that 044 and see if that resolves it. Or at least install a fuel pressure guage to verify it is a fuel delivery issue.
09-21-2012, 10:53 PM
#64
Burning Brakes
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Swapped the pump and added a fuel gauge and it now runs worse. Its like its chocking out... I am going to swap relays tomorrow to see if the replacement 53s I put in are just faulty...
This is so much fun chasing a mystery problem... like drinking gas
I have some other issues from the painter (lights again don’t work, windows don’t go down, etc....) so I am going to also check the grounds on the car to see if i have a short somewhere... not sure if that would cause this issue, but i want to rule that out as well.
I am also going to swap that fuel dampener in the front that may be suspect...
These babies run so great, until you start toying with them... aurgh.... but she looks really pretty
09-22-2012, 01:36 PM
#65
Burning Brakes
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OK, so I changed out the fuel pump, the relays and the front Fuel Inj Pressure Damper.
It now runs worse than it did with the 044 pump. Its like the 044 pump helped overcome the issue I have now with increased pressure (assumption, no real proof).
The 88 S4 external pump chokes out early. I get on it and i can run up to 4K, but then it sputters and chokes out completely until I let up and keep it under 2k.
This problem is similar to the original problem when the in tank pump was completely shot, causing a void in fuel and I could not load up, but I have the in tank replacement filter (that big one from here) a new fuel filter and the lines are all new.
The car was running right until I took it for paint and did the top end... I checked to see if I had bent lines that would act as restriction, but found none. The fuel pressure gauge I put in shows 40-50psi at any given time (I did see it drop to 20 for a split second when I revved it). It never chokes out without load (in gear and driving).
Having the 044 pump work and I could run the car hard until is shut off (like no fuel)... could the filter be shot and collapse internally where it is restricting? ... but then should I now have pressure drop at the engine?
Injectors are all fresh cleaned. I did nothing to the two rear motor dampeners, other than take them in and out a few times while messing with vacuum leaks on the top refresh...
I have eliminated:
o MAF (know good one
o LH (known good one)
o Fuel pump - changed twice (hope 3 pumps in a row would not be bad)
o Front dampener (know good one)
o Relays (as best as I can tell with ones that were working - swapped twice)
o Fuses (none are blown)
o Pinched fuel lines (I did not see any)
o I even ran it without the gas cap to try to see if it was locking up under vacuum
What I have not done:
o I have not checked for spark, but it runs without cause until I load it hard over 4K
o I have not re replaced the fuel filter
o cleaned the fuse and replay panel yet (but this baby ran strong before the paint and top refresh)
When I did the top end refresh, I replaced:
o CPS
o Knocks
o Throttle sensor
o gaskets
o vacuum lines
o rebuild throttle body
o Did not replace the Idle Control Valve (but cannot imagine I would need to or this would relate)
o Cleaned (professionally) the injectors
o Fuel lines
o Temp II sensor and cleaned the powdercoating off
o New temp sensor and cleaned the powdercoating off
When I redid the front of th motor (and it ran perfect after) I replaced:
o Coils
o Plugs
o Wires
o Caps
o belts
o water pump
The motor just acts like it is starving under load...
I am running out of ideas.... my next stab will have to be the fuel filter...
Anyone else have ideas?
It now runs worse than it did with the 044 pump. Its like the 044 pump helped overcome the issue I have now with increased pressure (assumption, no real proof).
The 88 S4 external pump chokes out early. I get on it and i can run up to 4K, but then it sputters and chokes out completely until I let up and keep it under 2k.
This problem is similar to the original problem when the in tank pump was completely shot, causing a void in fuel and I could not load up, but I have the in tank replacement filter (that big one from here) a new fuel filter and the lines are all new.
The car was running right until I took it for paint and did the top end... I checked to see if I had bent lines that would act as restriction, but found none. The fuel pressure gauge I put in shows 40-50psi at any given time (I did see it drop to 20 for a split second when I revved it). It never chokes out without load (in gear and driving).
Having the 044 pump work and I could run the car hard until is shut off (like no fuel)... could the filter be shot and collapse internally where it is restricting? ... but then should I now have pressure drop at the engine?
Injectors are all fresh cleaned. I did nothing to the two rear motor dampeners, other than take them in and out a few times while messing with vacuum leaks on the top refresh...
I have eliminated:
o MAF (know good one
o LH (known good one)
o Fuel pump - changed twice (hope 3 pumps in a row would not be bad)
o Front dampener (know good one)
o Relays (as best as I can tell with ones that were working - swapped twice)
o Fuses (none are blown)
o Pinched fuel lines (I did not see any)
o I even ran it without the gas cap to try to see if it was locking up under vacuum
What I have not done:
o I have not checked for spark, but it runs without cause until I load it hard over 4K
o I have not re replaced the fuel filter
o cleaned the fuse and replay panel yet (but this baby ran strong before the paint and top refresh)
When I did the top end refresh, I replaced:
o CPS
o Knocks
o Throttle sensor
o gaskets
o vacuum lines
o rebuild throttle body
o Did not replace the Idle Control Valve (but cannot imagine I would need to or this would relate)
o Cleaned (professionally) the injectors
o Fuel lines
o Temp II sensor and cleaned the powdercoating off
o New temp sensor and cleaned the powdercoating off
When I redid the front of th motor (and it ran perfect after) I replaced:
o Coils
o Plugs
o Wires
o Caps
o belts
o water pump
The motor just acts like it is starving under load...
I am running out of ideas.... my next stab will have to be the fuel filter...
Anyone else have ideas?
Last edited by Spun; 09-22-2012 at 02:18 PM.
09-22-2012, 02:55 PM
#67
Burning Brakes
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09-22-2012, 02:58 PM
#68
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You've mentioned "fuel lines" (that have been replaced) a few times. What was replaced, and with what? I'm wondering if there's a possibility of a generic replacement hose that's more likely to kink and that is on the verge of kinking, but maybe only kinks under certain dynamic conditions.
If you have any doubt about any hoses anywhere doing that, you can always try kink-proofing them by wrapping them with stiff wire like this to see if that makes any difference:
(This was a temporary kluge and was replaced with the proper formed hose shortly thereafter.)
Also, any possibility that a dodgy fuel pump check valve could lead to these symptoms?
If you have any doubt about any hoses anywhere doing that, you can always try kink-proofing them by wrapping them with stiff wire like this to see if that makes any difference:
(This was a temporary kluge and was replaced with the proper formed hose shortly thereafter.)
Also, any possibility that a dodgy fuel pump check valve could lead to these symptoms?
09-22-2012, 03:15 PM
#69
Burning Brakes
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You've mentioned "fuel lines" (that have been replaced) a few times. What was replaced, and with what? I'm wondering if there's a possibility of a generic replacement hose that's more likely to kink and that is on the verge of kinking, but maybe only kinks under certain dynamic conditions.
If you have any doubt about any hoses anywhere doing that, you can always try kink-proofing them by wrapping them with stiff wire like this to see if that makes any difference:
(This was a temporary kluge and was replaced with the proper formed hose shortly thereafter.)
Also, any possibility that a dodgy fuel pump check valve could lead to these symptoms?
If you have any doubt about any hoses anywhere doing that, you can always try kink-proofing them by wrapping them with stiff wire like this to see if that makes any difference:
(This was a temporary kluge and was replaced with the proper formed hose shortly thereafter.)
Also, any possibility that a dodgy fuel pump check valve could lead to these symptoms?
I am wondering if I have some how kinked the or twisted the metal like at the pump... I ordered another filter that will be available in 2 hrs. I am going to swap that and look hard at all the metal lines again...
On the check valve, I'm not sure.
09-22-2012, 03:25 PM
#70
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The issue in this case is that the TEMP-II sensor has two temperature sensors - one for each male pin - each of which grounds to the car's body via the hex-head base of the sensor body through the crush ring to the water bridge to the water bridge bolts to the heads to the block to the engine ground strap.
Powder coating can be high-resistance and therefore interfere with the ground circuit. Initially, there's enough metal in the sensor to give a reasonable resistance reading. But as the engine runs, the ECU's circuits suck electrons out of the metal of the sensor body and with the high-resistance of the powder coating electrons can't flow nicely through the sensor to the ECUs from the body.
[...]
If you PC the water bridge you need to make sure to remove the PC from the sealing surface underneath the TEMP-II sensor and from the washer surface underneath at least one of the water bridge bolts.
Last, some PC can LOOK like bright aluminum when you Dremel it and provide a good ground path until it goes through some temperature cycling.
A multimeter resistance check from the TEMP-II to a ground point is not enough of a test.
Powder coating can be high-resistance and therefore interfere with the ground circuit. Initially, there's enough metal in the sensor to give a reasonable resistance reading. But as the engine runs, the ECU's circuits suck electrons out of the metal of the sensor body and with the high-resistance of the powder coating electrons can't flow nicely through the sensor to the ECUs from the body.
[...]
If you PC the water bridge you need to make sure to remove the PC from the sealing surface underneath the TEMP-II sensor and from the washer surface underneath at least one of the water bridge bolts.
Last, some PC can LOOK like bright aluminum when you Dremel it and provide a good ground path until it goes through some temperature cycling.
A multimeter resistance check from the TEMP-II to a ground point is not enough of a test.
09-22-2012, 05:38 PM
#71
Burning Brakes
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Ok, fuel pump out and ready for the new one. I do not think this is the issue. Fuel drained from the filter with no issue...so I decided to pop the fuel gauge and take a look at the screen filter in the take... It looks like a swamp in there with the crap in the tank. WTF!!! I cleaned that tank myself like a champ. I could have drank
from it... And the amount of **** in there is crazy... This could easily be the problem...
from it... And the amount of **** in there is crazy... This could easily be the problem...
Last edited by Spun; 09-22-2012 at 05:59 PM.
09-22-2012, 06:02 PM
#72
Nordschleife Master
Had the same.
Now I would add additives to loosen the 'gunk' and get it out to the fuel filter. After this being done, then I would change out the dirty filter.
Add a bottle of Techron and 6 oz. of MMO (Marvel Mystery Oil) to each 1/2 tank of fuel (Stan's {MrMerlin}) recommendations). Do this 5-6 times, meaning you'll put some miles on
This really worked well for me. After going through many diagnostics I ended having fuel starvation at the outlet.
Now I would add additives to loosen the 'gunk' and get it out to the fuel filter. After this being done, then I would change out the dirty filter.
Add a bottle of Techron and 6 oz. of MMO (Marvel Mystery Oil) to each 1/2 tank of fuel (Stan's {MrMerlin}) recommendations). Do this 5-6 times, meaning you'll put some miles on
This really worked well for me. After going through many diagnostics I ended having fuel starvation at the outlet.
09-22-2012, 06:06 PM
#73
Rennlist Member
Where
Where have you been buying your fuel?????
If it's one particular station, I'd take the crapped up bits and beat the owner with them.
If it's one particular station, I'd take the crapped up bits and beat the owner with them.
Ok, fuel pump out and ready for the new one. I do not think this is the issue. Fuel drained from the filter with no issue...so I decided to pop the fuel gauge and take a look at the screen filter in the take... It looks like a swamp in there with the crap in the tank. WTF!!! I cleaned that tank myself like a champ. I could have drank
from it... And the amount of **** in there is crazy... This could easily be the problem...
Attachment 666045
from it... And the amount of **** in there is crazy... This could easily be the problem...
Attachment 666045
