JD928_S4

Hey all,
This morning I had some errands to run and got up early. The car ran great for like 20-30 mins to my destination. I was there for about an hour and got back in the car and it wouldn't start. I would kick and wanna start but would just shut right off after like 2 seconds. That or it would start and idle real low like 300 rpm and almost die for like 10 seconds then it would just quit. I tried even coaxing it with the throttle but it would cause the car to die. After several tries it just started cranking with no pop at all. Ideas?

Thanks in advance!
Jacob

the flyin' scotsman

what year and model is the car?

JD928_S4

1989 S4 auto with 156000 on the clock sorry I left that out

SteveG

Sounds like fuel related. I would jump the FP relay first or test horn, if that works, replace FP relay with horn relay. Do you still have the relay chart in the sleeve over the access panel? If not go to 928gt.com. Print the schematic Dave has provided for your MY.

JD928_S4

Yep I have the relay chart and I tried jumping the relay with a wire and didn't seem to make a difference. Problem is the car is like 5 miles away stranded and I can't get back to it till later. Im trying to compile as many ideas hoping that I could avoid having it towed to my apartment. Thanks for the help so far!

the flyin' scotsman

There is lots of gas in the tank?

The FP relay is interchangable with many............the horn relay is a good choice. With the relay jumpered the pump should constantly run. Pull the air filter lid and make sure nothings obstructing flow. If you have a helper perhaps pull a spark plug or 2 and check for ignition.

The relay for the fuel computer is the same as the FP relay..............swap it with horn, defrost, HVAC etc.

SteveG

Have to ask, fuel in tank? How old is the batt?
When you jumped the fp, did you hear it run?
Pumps usu do a slow death, but you need to know if fuel is getting pumped, could be filter or plugged pump.
I would pull plug, wet or evidence of fuel present, might mean ignition relay. Determine if you have spark? If both those relays are good and you have spark, I defer to others re computer problem. There is a condition, hot-no start. It will start after 20 mins to 1 hour. Maybe someone can jump in here re computer, or search for same.

I had a ground problem, from long cold, it would start w/starter fluid, got worse, wouldn't start at all. Your car sits out? Check batt ground + others in engine bay, including coils and ground to coils.
Good luck.

JD928_S4

Well I think there is a 1/4 tank unless my gauge is suddenly inaccurate, the batt is new as of a few months ago and cranks real hard even after a bunch of tries. Yea car does sit outside. As of not Im gonna check the coil grounds, other grounds in the engine bay, as well as switching the ignition and fuel pump relays with HVAC and Horn. Thanks this is all very helpful. Keep them ideas comin!

Jacob

John Speake

Be careful jumping the FPR as if you get the connections wrong you will kill the FPR driver stage in the LH ECU.

9two8

Not saying this is the fault, but when was the last time you changed the fuel-filter ?..., I had very similar symptoms, although mine would start and immediately die,.... turned out that the filter innards had collapsed constricting the fuel flow, yours maybe blocked ? new filter/lines cleaned, and she fired up back to normal.

Ken
80 928s
5 Speed
UK

Shark Attack

ECU, (brain)
If you turn on the key can you here clicking under the hood? specifically the injectors. if you can hear this, its a sure thing, however, if you dont hear it still doesnt mean that this is not the problem. This is exactly how my 89 acted when the ECU was bad. Some really good troubleshooting can be found here:

http://electronikrepair.com/page6.html

Leon Speed

I'm guessing it's either the MAF or the LH. If the previous tips don't work, try unplugging the MAF, changing the MAF and/or LH with a loaner.

JD928_S4

Hey guys thanks again for the advice! Now the question is Is there anyone in the Buffalo NY area that would be willing to let me try their LH and or MAF? That or the Albany NY area I travel to albany frequently and could pick it up / bring it back. I would really appreciate the help.

Thank you,
Jacob

Shark Attack

you are asking a lot. both parts are quite expensive and what if another condition in the car is ruining the part? then you fry the other guys part. Did you look at the website in my last post and try some of his troubleshooting ideas. You can also send the LH to him and he will test it out.

Mrmerlin

if you want to test things its better to use your parts in a car thats running well, this let the good running car have a chance to either confirm or fail the part being tested