88 S4 Hard warm starting issue “not leaky injectors” **Repaired**
12-31-2006, 09:21 PM
#16
Racer
Thread Starter
What a way to end the year 
over in Bill’s driveway working on my 928! Thanks again Bill… 
I’ll get a pressure regulator ordered up on Tuesday – looks like I need P/N 928 110 198 04, runs around $90 bucks at 928 International
over in Bill’s driveway working on my 928! Thanks again Bill… I’ll get a pressure regulator ordered up on Tuesday – looks like I need P/N 928 110 198 04, runs around $90 bucks at 928 International
01-01-2007, 07:06 PM
#18
Racer
Thread Starter
I pulled the pressure regulator and to me it seems bad, if I plug one side and blow in the other I have air flowing out of the fitting that goes back to the tank. Bosch part # on the old one is 0 280 160 297 which looks to cross to the Porsche # Now for the hard part, I had something fall into the belly pan 
I better go find what dropped down there 
Happy New Year to everyone…
I better go find what dropped down there Happy New Year to everyone…
01-02-2007, 09:25 AM
#21
Racer
Thread Starter
I hear you Bill I did find what dropped and to my surprise it looks to be one of the 19mm bell housing bolts. Ouch that a big one to work loose. I have the fuel pressure regulator out and will order the replacement today. Then I’ll be ready for the new Boge Reds, rotors etc 
I did find what dropped and to my surprise it looks to be one of the 19mm bell housing bolts. Ouch that a big one to work loose. I have the fuel pressure regulator out and will order the replacement today. Then I’ll be ready for the new Boge Reds, rotors etc
01-02-2007, 10:06 AM
#22
Team Owner
Thats great i Hope this fixes the problem , please let us know, Stan
01-02-2007, 10:42 AM
#23
Supercharged
Rennlist Member
Rennlist Member
Join Date: May 2002
Location: Back in Michigan - Full time!
Posts: 18,925
Likes: 0
Received 62 Likes
on
35 Posts
I finally got done reading this entire thread. What a great diagnosis! Sure sounds like you guys got this narrowed down to the culprit. PLease post the outcome. I'm putting this in my hard start folder. 
01-02-2007, 09:57 PM
#25
Racer
Thread Starter
Hey Guys,
Will do, I talked with Mark A. at 928 International this afternoon and just got the UPS Ship notice so the part is on the way
I'll keep you posted
Will do, I talked with Mark A. at 928 International this afternoon and just got the UPS Ship notice so the part is on the way
I'll keep you posted
01-03-2007, 02:26 AM
#26
Under the Lift
Lifetime Rennlist
Member
Lifetime Rennlist
Member
Originally Posted by edco
I hear you Bill I did find what dropped and to my surprise it looks to be one of the 19mm bell housing bolts. Ouch that a big one to work loose. I have the fuel pressure regulator out and will order the replacement today. Then I’ll be ready for the new Boge Reds, rotors etc
I did find what dropped and to my surprise it looks to be one of the 19mm bell housing bolts. Ouch that a big one to work loose. I have the fuel pressure regulator out and will order the replacement today. Then I’ll be ready for the new Boge Reds, rotors etc
01-03-2007, 12:59 PM
#27
Rennlist Member
Join Date: Jun 2006
Location: Vancouver, Canada
Posts: 165
Likes: 0
Received 0 Likes
on
0 Posts
89' Euro S4
I've been reading your thread and it sounds like you have the same symptoms as I've been having. I started with the easy stuff and narrowed it down to the pressure regulator after reading some other posts with the same issue. I was having trouble starting the car hot and cold and it just didn't seem to be running well.
I started by replacing the fuel filter, fuel pump check valve, Temp II Sensor, tested all the resistance levels to the LH and EZK. Everything checked out OK. However, the problem was still there. Last summer I pulled the injectors and had them cleaned and balanced, so I ruled them out.
I kept suspecting that the FPR was bad but was also worried about a bad brain. Didn't want that!
I finally pulled the vacuum hose on the FPR and the Dampners and there was alot of gas coming out of the vacuum hole on the FPR! No gas from the Dampners so I figured it must be the FPR.
Last night I replaced most of the relays and the FPR and Voila! Ran it hot and restarted fine. Started it up this morning cold and the car runs like a dream! Cost me a few hundred bucks but the car runs better than it ever has.
I suspect you have the same problem. Good Luck!
Brent
I've been reading your thread and it sounds like you have the same symptoms as I've been having. I started with the easy stuff and narrowed it down to the pressure regulator after reading some other posts with the same issue. I was having trouble starting the car hot and cold and it just didn't seem to be running well.
I started by replacing the fuel filter, fuel pump check valve, Temp II Sensor, tested all the resistance levels to the LH and EZK. Everything checked out OK. However, the problem was still there. Last summer I pulled the injectors and had them cleaned and balanced, so I ruled them out.
I kept suspecting that the FPR was bad but was also worried about a bad brain. Didn't want that!
I finally pulled the vacuum hose on the FPR and the Dampners and there was alot of gas coming out of the vacuum hole on the FPR! No gas from the Dampners so I figured it must be the FPR.
Last night I replaced most of the relays and the FPR and Voila! Ran it hot and restarted fine. Started it up this morning cold and the car runs like a dream! Cost me a few hundred bucks but the car runs better than it ever has.
I suspect you have the same problem. Good Luck!
Brent
01-03-2007, 02:09 PM
#28
Under the Lift
Lifetime Rennlist
Member
Lifetime Rennlist
Member
Brent:
Similar except we have no fuel coming out the vacuum holes. We just have a FPR that is able to maintain pressure when the pump is running but is not completely sealing the return orifice when the pump is turned off.
If we all would just have followed the WSM testing procedure, we could have avoided replacing a lot of other parts, as the FPR return is the FIRST thing you check if the fuel pressure does not hold. I was focusing on it being either the check valve or the injectors and overlooked the FPR until I checked the WSM when neither of the former fixed the issue.
Similar except we have no fuel coming out the vacuum holes. We just have a FPR that is able to maintain pressure when the pump is running but is not completely sealing the return orifice when the pump is turned off.
If we all would just have followed the WSM testing procedure, we could have avoided replacing a lot of other parts, as the FPR return is the FIRST thing you check if the fuel pressure does not hold. I was focusing on it being either the check valve or the injectors and overlooked the FPR until I checked the WSM when neither of the former fixed the issue.
01-03-2007, 02:16 PM
#29
Rennlist Member
Join Date: Jun 2006
Location: Vancouver, Canada
Posts: 165
Likes: 0
Received 0 Likes
on
0 Posts
Bill,
Looking forward to hearing how the new FPR works! As I mentioned your issues sounded very similar to mine. If the new part works, excellent, otherwise back to the drawing board! And your right, the WSM testing procedures do save a lot of headaches.
Brent
Looking forward to hearing how the new FPR works! As I mentioned your issues sounded very similar to mine. If the new part works, excellent, otherwise back to the drawing board! And your right, the WSM testing procedures do save a lot of headaches.
Brent
01-05-2007, 01:16 AM
#30
Racer
Thread Starter
The fuel pressure regulator arrived today and I installed it tonight, started the car to check for fuel leaks and everything looks good. I need to pull the belly pan to reinstall that darn bolt. I’ll button it up tomorrow and report back.
At some point I’ll need to get with Bill and put his fuel gauge on there to see if we solved the 60# to Zero lbs of pressure in 15 seconds problem , well that and hope she starts right up warm…
At some point I’ll need to get with Bill and put his fuel gauge on there to see if we solved the 60# to Zero lbs of pressure in 15 seconds problem
, well that and hope she starts right up warm…