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-   -   Died at a stoplight and will not start... (https://rennlist.com/forums/944-turbo-and-turbo-s-forum/209356-died-at-a-stoplight-and-will-not-start.html)

gregeast 06-13-2005 12:23 AM

Died at a stoplight and will not start...
 
My symptoms are that my '87 951 car just died at a stoplight while idling and then would not restart. It turns over (at what sounds like 'normal' speed) but never fires.

After lots of searching for ideas on the list, so far I've:

- Determined that there is spark at the plugs with a spark tester
- Determined that there is fuel at the fuel rail. Pulled the hose off the FPR and had what appeared to be lots of gas when I turned the motor over. Will probably buy a fuel pressure gauge just to be certain.
- Determined that the t-belt is still in one piece by inspection through the view hole.
- Replaced the DME relay with a new one
- Determined that the tach is 'bouncing' when I try and start it.

As of yet, still no joy. I'm going to try a new fuse for the DME and try and put a multi-meter on the DME connector as well to determine if there is power to it..

Any other thoughts, suggestions, nuggets o'wisdom?

Update: Looks like I'm in the same situation as J Chen. The belt is sitting on the sprocket but the sprocket is not turning. I'm going to pull the covers this weekend and have a look but it looks like I have a broken t-belt. I'll be thrilled if the valves aren't bent but I'm not holding my breath, looks like I have a bit of work ahead of me...

Thanks to all for the thoughts and suggestions!


Greg

testarossa_td 06-13-2005 12:47 AM

Only a nugget. TPS

NZ951 06-13-2005 02:55 AM

I put my 2 cents on your reference sensors.

gregeast 06-13-2005 09:14 AM

Testarossa: Good thought, I'll double check the TPS. I replaced it about 10 months ago but who knows.

NZ: It was my understanding that if the tach bounced when I try to start it and if I have spark at the plugs that it's likely not the reference sensors. Having said that, I think I'll check them as well.

Thanks guys,

Greg

944Ecology 06-13-2005 12:53 PM

for a turbo, KLR box.

gb

fortysixandtwo 06-13-2005 01:09 PM

Was it raining or had been raining when this happened? I had the same symptoms when the computers in my car had some water carry over due to a rotted battery tray.

quinnfiske 06-13-2005 01:20 PM

I had this same problem only it would die while driving also. I had spark and fuel as well. It turned out to be a bad DME. The silly thing was sending out an incorrect timing signal and letting the engine die. Try taking a timing light (remember those?) and shine it in the inspection hole for the cam belt. I could watch mine retard the timing until it died.

Dr. Dynamics 06-13-2005 02:44 PM

Try tapping a little the DME, on the passenger side. Mine had a cracked weld spot on the computer board. It had to be reheated and gone was the problem. Who knows...Good luck..

gregeast 06-13-2005 07:03 PM

Based on multiple inputs, I'm starting to suspect the DME as well. There's definitely fuel at the rail but I'm not smelling gas like I'd think I would be if the injectors were dumping fuel into the cylinders and then not getting ignition.

It was not raining when it happened although it started raining shortly thereafter. The only semi-unusual thing that happened that day was that I took my boss for a ride to lunch. He's a big boy and I'm wondering if maybe he pushed on the floorboard getting in and out. I don't typically have a passenger with me and if I do, it's my wife and her legs probably never reach the floorboard. I realize that's a bit of a stretch but I think I've check the obvious stuff already...

I think the next step is to try and determine if the injectors are working, I think there's a way to use a test light to see if the injector is getting a signal. Also going to inspect the injector wiring harness and the DME connector and board.

Please keep those good ideas coming and I'll promise to keep everyone updated, including what the ultimate solution is.

Thanks again,

Greg

docwyte 06-14-2005 01:20 AM

If my 951S DME will work, we can toss it in to see if that's the problem with yours...

daniel951 06-14-2005 07:46 AM

dam these cars. mine is acting up too. was driving on the road after getting on it a little bit back fired and kept wanting to die out. My car would do the same thing start up and die instantly. it ended up being a spark plug wire loose and the car idles fine but not it lacks power and wants to choke out all of the time. sorry to hear about the car greg hope you get it running.

quinnfiske 06-14-2005 11:28 AM

You can test the injectors with a gizmo called a noid light. I got one for a couple of bucks at an Autozone. It fits the connector on Bosch injectors. It is an LED and not a lamp. It should glow when you crank the engine. You can also hear them softly clicking when you crank the engine.

Don't overlook the KLR. I bought one that turned out to be fried and the car won't even fire with it. You can jumper past it to test it. I will look all that up if you wish.

R.B. 06-14-2005 11:48 AM

I had the same issue last year. I reoldered my DME and has been working fine since. If you can borrow one, it is a quick diagnosis.

R.B.

gregeast 06-14-2005 01:57 PM

quinnfiske: Good heads up on the noid light, I'll stop by Autozone tonight. When you say KLR, do you mean the KLR chip itself or the board that it's plugged into?

R.B. When you resoldered the DME was it obvious where the break was? I think I'll try swapping in DocWyte's as a quick test and then go from there.

Thanks guys, I really appreciate the help!

Greg

R.B. 06-14-2005 02:03 PM

No on mine it was not obvious. I used a magnifying glass but could not really see any cracks, burns or cold solder joints. I basically started with the large transistors and any heat sink parts. Any solder joints that looked minimal as well.

HTH
R.B.


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