peterjcb

Everything was running fine on Saturday, I ran some errands around town and later that night I washed and waxed the car for the auto show on Sunday. Previous to today I have been having some "return to idle" problems where the RPM"s would drop when I stopped and the engine would stall out.
I needed gas so Saturday night I took it to the gas station and before I got there the car started running very rough and wouldn't rev up. I barely made it back home. It will barely start now and when it does start, I can't bring the RPM's up and the engine just dies out.
I'm getting spark from the wires so I'm thinking more towards fuel problem.
What's the first step in checking for fuel problems?

peterjcb

I'm wondering if it's my fuel pressure regulator or possibly the throttle body sensor?

Chris_924s

have you tried swapping in a new DME Relay?

peterjcb

I don't have an extra one but just where is the DME relay?

Gear Dog

Look under your hood in the fuse box. It's easy to find as it has DME stamped on the top of it.

peterjcb

Thanks Ken.
I may be able to swap out a buddy's DME to test but I don't think that's the problem. Right now I leaning primarily toward a bad fuel pressure regulator or secondly a bad idle control valve.
Any other suggestions before I order this morning???

black944 turbo

Peter Tuesday and Thursday I get out around noon, so if you want to swap the relay on one of those days let me know.

peterjcb

Hi Richard,

Sounds like you had a great time at the show yesterday, sorry I missed it.

The FPR for my "S" is different than any other FPR I see listed although it looks exactly the same. I feel pretty confident that it's the problem. But just to eliminate the DME relay as a source of the problem it would be great if you could run by sometime on Tuesday to do a test swap.
In the meantime I'm going to order a FPR so I can hopefully get my car going again. It's about $70 from either Paragon or Pelican.
Talk to you Tuesday.
Peter

black944 turbo

Sounds good, I will call you tomarow.

peterjcb

Thanks Richard, you've got my cell # - call me whenever you're around. Hopefully it will be a bad DME. I'm going to hold off on ordering up the FPR until we test out the DME.

95Juan

i've had the same problem on both my 944's (n/a and turbo), it was the fuel pump wiring. the power to the fuel pump was running through an oxidized wire, and i just soldered it onto the fuel pump, fixed the problem, instantly.

peterjcb

Exactly where did you find the problem wire?

95Juan

at the fuel pump, take off your rear passenger wheel, and you should have free access to it.

peterjcb

I swaped out the DME relay this morning and it didn't make any difference.
I won't get a chance to check it out til tonight. I going to see if I can hear if the fuel pump is working while I have someone crank it up.
The only way I can keep the car running, is to floor the accellerator and even then it barely idles....As soon as I take my foot off the accelerator it dies.
BTW, I"ve never pulled plugs on this car. What size socket does it take, everything I have doesn't seem to work.

peterjcb

I eliminated the Throttle Position switch by testing for resistance at the DME wiring harness plug. Everything read OK there. I'm getting spark and gas and I eliminated the DME by swapping it out with a known working one.

However, after I cleaned the connections on the Air Flow Meter and tried the car again, I actually got the engine to rev up...something that I couldn't do for a couple of days and it will actually idle very rough at about 700 RPM, so I think that the problem may lie with the AFM.
Does anyone have experience with the AFM? There's a detailed procedure at Clarks-garage for testing and cleaning it. I'm going to work on that tomorrow night.