924Board.org

jimbo924s · Joined: 24 Jan 2004 Posts: 5

I have a 87 924s

. It is in the shop and they can't figure out whats wrong with it.

It will run fine then all of a sudden it shuts down. Like it's not getting any fuel. All the electrics work. It will not start, then if you let it sit for a few mins. It will start back up and run fine again for a while then do it again. It idles fine but it will be very rough when you start off, then catch and run fine, then do it again. Its weird! They don't know whats wrong. It seems that my car does things that they have never seen a prosche do before, and thats all they work on. Can anyone help????

Paul · Posted: Sat Jan 24, 2004 11:32 am Post subject:

Check the grounds under the heater valve.

If the grounds are good have them do the DME Test Plan in the factory manual. If they look at you like you're nuts, run to a dealer.

Don't just start throwing parts at it, BTDT.

Lousailor · Joined: 04 Sep 2003 Posts: 16 Location: San Diego

Jimbo,
Have them look at the flywheel sensors. They have connectors at the back of the motor, just next to the firewall near the intake manifold, and plug into the top of the bellhousing. My '87 924S had the same problem. Had a mechanic who didn't know what to look for, he replaced the cat (don't ask), the coil, wires, plugs, rotor, cap. Couldn't get the car to start up at work so I had it carted home on a flatbead. Bought a cheap spark tester at the local parts store. Even with a known good coil, no spark. Before wedging out the DME relay, I traced the sensors (two twin style, side by side so don't mix them up), and when I finally wiggled them out, discovered the end was covered with gunk and metal particles (they are magnetic). Cleaned and rebolted them one at a time, and I haven't had a problem since (over a year ago). Good Luck
_________________
'87 924S (Crunch/Rebuild)
'85 944 (Beater)

jimbo924s · Joined: 24 Jan 2004 Posts: 5

Thanks both of you!!!! They have tried both things, no luck. They have called around the country to other mechs. It's just weird!!!!! The car will start and run a ways then it will start to shut down. All the electrics work, but the car stops running. Its like something heats up and then shuts it down, you sit for a bit, it start back up and does it all over again. I think it's starting to frazzel them also. My car is possessed.

dgz924s · Joined: 03 Nov 2002 Posts: 592 Location: Kansas

Well if the DME and sensors are ok!?

Have you looked at the FP and Idle control valve. ICV is located under the intake manifold and yes you do need to pull the intake to get at it. Dal
_________________
Dal Glassinger

Paul · Posted: Tue Feb 10, 2004 12:47 pm Post subject:

Take your fuel filter off, drain the gas out of it, and then shake it, if it rattles replace it!

Did you do the DME test plan in the factory manual yet?

Sleykin · Posted: Tue Feb 10, 2004 1:19 pm Post subject:

Could be too much fuel pressure. Try removing one injector plug and running it that way. if it runs without faulting (other than the obvius miss on 1 cylinder) you may have a problem with the fuel pressure regulator or a vacuum hose to the regulator leaking and causing the pressure to slowly build till it can't fire the injectors anymore. Too much pressure oveloads the electric control on the injectors and they fail to fire. Unplugging one injector reduces the load and lets them fire if that is what's happening.
_________________
Glenn Neff
Medford, OR
87' 924S

jimbo924s · Joined: 24 Jan 2004 Posts: 5

Thanks guys!!!!!
Here is an up date.
1. The DME relay replaced.
2. A new brain hooked up.
3. All sensors check out fine.
4. All grounds check out fine.
It still shuts down. Now, it will idle all day long, but as soon as you put a demand on it like going up a grade or sometimes just accelerating will cause it to shut down,or run rough before it shuts down. When it does shut down, if you try to start it right away, it will not. You let it sit for 30 secs.it will start right up

Now one of the bad things is that it is an intermittant thing. You have to be driving it to have it happen. It will idle all day long.
Oh by the way this is an automatic, if that makes a differance.

gohim · Joined: 02 Nov 2002 Posts: 4459 Location: Rialto, CA

Was this car parked for a while?

Did you buy it in ths condition?

How old is the gas in the tank? Is there any chance that it is contaminated?

Still sounds like it has a fuel problem. Have you tried Paul's suggest and replace the fuel filter?

jimbo924s · Joined: 24 Jan 2004 Posts: 5

No, I have had the car some time now. It has been running fine until this happened. I have gotten gas from the same place I always do. They are changing the filter Mon., but they are very doubtful that is the problem. You never know sometimes the most simple things are the answer.

Paul · Posted: Sat Feb 14, 2004 2:27 pm Post subject:

Sometimes the filters fail inside mechanically and the loose parts block the outlet. That's why I said to replace it if it rattles.

Tyrus · Joined: 18 Feb 2004 Posts: 10 Location: South Carolina

It sounds like the fuel filter is loading up. It works then dies thens sits and is better. Try the quick fix first. I've seen that on cars of many makes.
Good luck

jimbo924s · Joined: 24 Jan 2004 Posts: 5

It has finally been fixed!!! It turned out to be the fuel regulator, which I have been told that, it is so very uncommon of a item to have problems with,that it took awhile to find it as the problem.

Well it works now!!! I still have to replace the heater core. I hear that, thats a bitch but, I'll tackel that one on my own. The worst part is dealing with the dash. Thanks for all your help! Once I start on the heater core I'll most likely be back asking for help.