Alpine951

I replaced the speed/reference sensors on my car earlier this year when the car had been off the road during the winter because I use to have no start issues and could usually cure it by pushing together the reference connectors a bit tighter. I also put in Lindsey racing harness wires for both sensors as the wiring at the connectors was falling apart. After replacing all this the car an great. 3 to 4 month later I had a turbo problem and pulled the turbo and put another one in. After getting it back on the road I experienced occasions on the highways where I would get a slight miss on the highway when I would hit a bump like at a bridge expansion joint. Then one day the car was running crappy and my wideband was all over the map. car stalled and took a while before it would start. I put it away for at least a month and then went back to it and it wouldn't start. I discovered some bad injector harness wiring at the injector connector and spliced in some new wire. starts and runs fine. The other day I pulled it out of the drive way and let it idle and it stalled. replaced the dme relay this week. been driving OK for a few days and now it didn't start. I fiddled with some wiring including the reference sensor connectors, disconnecting then plugging back together. no start. no tach bounce while cranking. then the tach bounced and the car started for a second then died. I tried pushing together the connectors a bit and then it started. could it be the new sensors and harness are already bad or would it be something else?

it eventually started and I put it back in the garage. gone and started it 3 times in the last few hours and it starts fine. The ecu is loose on the passenger footwell floor and when it was running I slapped the DME a few times to see if it would stall or miss. it didn't. kept idling fine. rapped on the new Wiltrin DME relay while it was running also but car kept running with no stall or miss. also right before this happened today I was out driving it and I reset the idle speed when I pulled it into driveway. don't see how this would matter.

Alpine951

lot of looks but no responses....... after hunting around I think I am going to crack open the DME and look for cracked solder.

Wipeout

Similar thing happened in a friend's race car, turned out to be a loose ground at the bell housing (not the big one, but a collection of smaller grounds).

Alpine951

dam... I'm going to need a magnifying glass. I can't tell if any solder is broken.

Alex Sol

Have similar experience as you.

ran the 951 at the track and took back home. wouldn't start.

replaced the speed/ reference sensors - ran but with misfire.

checked injector connections which are old and should be replaced

in process of re and re fresh turbo

don't have a start issues but do have this crank,stall,crank then start condition once in while

starter was also rebuilt

did you gap the speed/ reference sensors? not an easy job...

make sure you cover the inspection hole before doing anything in that area!! ask me why.... if you didn't read my thread on dropping a bolt in the hole then getting it jammed in the bell housing

good luck with the ecu - can you test a fresh one or put yours into a working 951?

Alex Sol

wipeout... any specific 'collection of grounds'?

is there a compiled list of these grounds somewhere on a separate thread?

Wipeout

There was a collection of several ground wires terminating at a single point on the bell housing. It was loose.

Here's the oft-posted ground locations image from the manuals: