Hey all, I have an 88 951 and I drove it this morning and after washing it, it will not start. At first I ran on what seemed to be on cylinder and now just cranks. I did not wash the engine so nothing got wet there. I know the dreaded DME relay problem on these cars but is there a way to jump the connections to either rule out the DME or confirm it to be the culprit? Any other ideas? Thanks in advance.

 

Sometimes the connections can develop corode. Clean & dry out any connections & you should be fine.

 

same thing happened to me. I was working on the car and I left the hood open over night. that night it rained a little. the next morning my car wouldn't start, it just made a clickling sound. I left the car alone and the next day it started fine.

 

Same here, first wash after the car was shipped to me I parked it in front of the house, went inside for a few minutes, came back and it wouldn't fire. I pushed it were I wanted to park it and next morning the same thing. After a warm day in the sun it fired right up. My problem turned out to be the connectors on the reference sensors side. The plastic was brittle and was falling apart, but only on the sensor side, the engine harness side was in great shape. Replaced the sensors and never had the problem again...were is some wood.

 

if it "cranks" you dont have a dme issue. Dont worry.... look for fuel spark and your get there.

 

Well, a new DME relay did nothing so that isn't it. I also checked for spark and that is fine too. I guess fuel is the next item to check.

 

Probably already done it, but are all the fuses ok?
I had the fuel pump fuse blow and it did much the same as yours. Ran rough briefly and then would crank but never fire. Loosen the big nut on the end of the fuel rail a little to see if gas is making it to the rail.

Good luck !

 

i was talking w/ a p-car mechanic and he told me about a 944 that wouldnt start and it was corroded flywheel position sensor(s). anyone know if that might be the culprit?

 

Yes, I did check the fuses (especially the fuel pump fuse) and they are all okay. I did crank the motor and could not hear the fuel pump...I think this is the culprit. I'll have to check to see if fuel is reaching the rail. My thinking is that the position sensors are okay since the car gets spark....but what do I know. I have a dead car in front of my house.

 

Sounds like DME

 

Well, I just finished up in the garage and took my car for a test spin. The fuel pump was the culprit for my no start problem.

 

I recall a mechanic saying something to the effect that if the tach was jumping while it was cranking, then it wasn't a problem with the flywheel sensor.. That was where it got the feed for the tach. If the tach lies there dead while cranking, The DME doesn't know the engine is turning, thus bad sensor. Make sense to anyone?

 

There are two sensors, one for RPM and the other is the reference sensor. If the TACH moves, the RPM sensor is generating a signal.

 

The sensor functionality link with the tach makes sense to me. Also, I'm beginning to think that the "bad" DME relays are what Urban Legends are made of....when I took mine apart, it did look pretty robust.

 

I wouldn't call it an urban legend, you might just find yourself stranded. A totally bad fuel pump can cause the symptom, but a relay is much cheaper and they do go bad. My brother's na went from first at the flip of the key to no start. Swapped in a spare known good dme, presto runno. Glad to hear you are running.