Need advice/ help with starting problem

Bob Besal · 05-25-2002, 08:33 AM

Trying to help ladyfriend get her 1991 944S Cab running again. After two years of "deep storage" / benign neglect sitting in garage, we've tried to prep the machine for market. Replaced battery, and finally silenced the alarm system thanks to tip by member Adrian Jaye (thank you!!!).

Cranked her up, started nicely, ran smoothly about 10 minutes, then just died. Fuel looked like it might be empty, so put a couple gallons in the tank, and tried to crank her again.

Turns over smoothly, but just doesn't even pop. Checked plugs--they're new, clean, and seemed dry. Got good spark from coil.
Just seems to be not getting any gas.

Question: With ignition on, should I be hearing an electric fuel pump? (Pretty fundamental question, but have no books or manuals). Pulled fuses for fans to make things quiet, and heard nothing.

Is their a fuel filter that's readily accessible? If the tank ran dry, is there something I needed to reset?

Seems to me it's going to be a fuel-oriented solution, but I'm open to all ideas...just a "carburator guy" trying to exist in a fuel-injection world.

Any ideas, threads to pull, etc will be really appreciated!

Bob Besal

drew1 · 05-25-2002, 11:04 AM

Hi Bob,

Fuel filter is back near tank.

Try spraying some ether & that would pin point it as a fuel problem.

I would see if I'm getting 12V to the injectors & get a noid light & check injector firing while cranking. If you're not then fuse or maybe relay (not sure if S computer runs off relay or not.)

If injectors are OK, check your fuel flow & pressure. I don't think the S has the nut & ball on the front of fuel rail like Regular 944, but a Scrade valve for pressure check. take hose off return on pressure regulator to check flow. From memory about 1/2 to 3/4 quart in 30 sec. If bad, then filter or pump would probably be it. The strainer in the tank gets clogged on start of sitting cars, but the pump would run if so. There is something that cuts fuel off when a presure is reached. I think it is in pump, but not sure.

drew1

Bob Besal · 05-25-2002, 11:41 AM

Drew---thanks. I'll look at all you suggest, but have to tell you, I feel like someone with "English as a second language!"

I'm famuliar a bit with the ether trick--question: where to spray?

I see you're in Greenwood. This car is in Charleston (Folly Beach). It's a Graphite Gray 91Cab, one owner, 90K miles. pretty fine shape--in case you know someone in the market.
Thanks,
Bob

Bob Besal · 05-25-2002, 02:36 PM

Okay, Drew. Found the large bronze B-nut at front of fuel manifold, removed it (and promptly dropped the ball into some intricate spot--thank heaven for lady's small hands to get it), and had some residual fuel come out. Is this where a pressure gauge would hook up? (no Schraeder valve there).

Have located pressure "regulators (air activated) one at either end of fuel injector manifold. I'm surmising the one at the rear is the supply side, and the front one ports to a "return" line...

Removed one of the injector leads--is this where I would check for 12VDC with a lamp?. Have checked all fuses, and all look good.

Thanks again,
Bob

adrian jaye · 05-25-2002, 02:53 PM

Quote:

Originally posted by Bob Besal
Trying to help ladyfriend get her 1991 944S Cab running again. After two years of "deep storage" / benign neglect sitting in garage, we've tried to prep the machine for market. Replaced battery, and finally silenced the alarm system thanks to tip by member Adrian Jaye (thank you!!!).

no prob !

Any ideas, threads to pull, etc will be really appreciated!

Bob Besal

Just wndereing if you sucked some dirt into the injectors, that length of storage, would see an ammount of rusting/moistrue etc in almost everything.

OK the fuel Filter should protect from this, but depends what and where stuff been sucked in.

Try pulling out the injectors and make sure there actually is fuel coming outta the suckers

I also thought there was a relay which stopped the fuel from flowing in the event of an accident (can't remember number, but it's on the fuse lid), are "all the fuses and relays making good contact, try pulling them out and re-fitting

Incase you could also try, powering down the car "pull the neg lead for 30'sce's) just in case the immoby's gonre screwy as well

good luck

ade

eligunn · 05-25-2002, 03:35 PM

If you didn't depressurize the system before you took out that plug and dropped that little ball, and the fuel did't come spraying out all over the place then your not getting fuel to the fuel rail.

newoldguy · 05-26-2002, 10:18 PM

If the car has been sitting for two years, and I'm assuming no gas treatment (i.e. Stabil), I would be concerned that the gas has "gone bad" and has clogged something along the way--fuel filter, injectors, all of the other stuff the guys have mentioned. In this case, you would have to start at the gas tank, drain it all out, and start cleaning stuff toward the working end.

Basically, its bad for gas to sit---even over the winter without a "treatment". This is true even for lawnmowers and such. You should always start the season with fresh gas.

Bob Besal · 05-27-2002, 07:51 AM

Thanks all for the pointers.
I tried removing the neg battery lead per Adrian's suggestion, but no luck with that. (Had to reset that darn alarm system again!)

I understand the "good gas gone bad" problem, too. What puzzled me was how it ran so nice for about 10-15 min., then just croaked. Guess thats just how it goes. Will get back to the task in a couple weeks. Still wondering--should I hear an electric fuel pump running/humming? Again have reseated appropriate fuzes and relays...
Thanks,
Bob

Eturbo924 · 05-28-2002, 03:44 AM

Bob
Have you replaced the DME relay. I am not sure if anyone noted this in previous posts. This can cause the car to shut down and refuse to restart. Since it is only a $20 or so part and you should be able to get one from Pelican it is worth a shot.

Eric

Bob Besal · 05-29-2002, 08:19 PM

Eric--thanks for that tip. I'll give that a shot, too.
Bob

Makis · 05-30-2002, 02:57 PM

You will need to remove the spark plugs, check them and see if they are fauled with petrol. It they are petrol is going there. Clean the spark plugs before placing them back and try starting the engine again.

Bob Besal · 05-30-2002, 06:49 PM

Makis--thanks. Did pull two of the four, and both looked like brand new. No fouling, and actually quite dry, which was leading me down the fuel problem path. I'll leave no stone unturned though--I appreciate your advice.
Bob

drew1 · 06-01-2002, 02:35 PM

Bob,

Yes that nut with the ball is where to check pressure. With the nut & ball removed, you can clamp a hose running to a guage & check pressure. Make sure hose is clamped real good at fuel rail & guage. Jump 30 & 87 in the relay socket, & pump should run. From memory, you should get between 35 & 40 PSI, it ought to go higher if you shut off the return line with vise grips or a clamp.

Take the return line loose from the regulator & hook another hose to it. In 30 sec you should be abe to get about 3/4 quart of fuel with pump running.

For the ether, take the booth off off the throttle body & open the butterfly & spray in the ether.

The injector lead, with 2 wires is where you check for 12V (one of them will have the 12.

Sorry to be back late with answer, have school ones using computer.

drew1

Bob Besal · 06-02-2002, 07:01 AM

Thanks Drew. I'll be back in the garage in about a week, and chek all this out.

Finally broke down and bought a Haynes 944 manual. While it only covers to '89, the photos look like some familiar geography, and all of the pointers I read here are stating to make sense! I appreciate your insights and support.
Bob

Bob Besal · 06-25-2002, 04:54 AM

Just needed to close this thread with all of you who were so helpful.

Had everything ready to try, but I first popped in a new DME/Fuel pump relay as suggested by Eric, and the darn thing fired up on the first try, and ran smoothly.

Thanks to all of you -- I appreciate your willingness to get me on the right track(s)--and I'm sure there's a bunch of them!

Bob Besal