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944 starting issue

Sean944nov

New member
Hi guys I’ve 1982 944 that refuses to start, everything that I know of from sensors to new Dme has been checked and nothing has worked it’s got spark fuel delivery the works yet will only fire up for 2 secs and dies .
any ideas are very welcome
 
Hi,
I know you said you have everything including feul delivery, have you checked to see if the injectors are actually engaging?

I am sure you must have checked these but worth asking.
Timing all correct?
Tach bounce Good? Assuming so as you have spark.

Have you checked the compression on each cylinder?




 
If it’s starting but dying I would suspect the ignition switch I.e. there is a live feed to the fuse box when the key is in the start position but not when it is in the run position.

 
As Nash said, you need spark, fuel and compression for it to run. If it stops then you are lacking one of the three. If you can find out which one is missing then you are on the way to diagnosing the problem.

Tom's ignition suggestion is a good one.


Oli.
 
Agree with ignition switch suggestion if it is dying as soon as you let go the key. If your 2 seconds of running are after you let the key go from start then its probably fuel rather than spark. Still may be ignition switch failing power to the fuel pump in run position OR it could be fuel pressure...e.g. will build enough pressure to start but can't supply enough fuel to keep it running. I'd check fuel pressure - if the pump is running but pressure no good then its not an electrical problem...it pump stops when switch released from start it will show up on the pressure test as well.
 
I would always start diagnostics with a 3 wire jumper in place of the DME relay just to take that out of the equation. With the jumper in you should hear the fuel pump whirring away and you know that the DME has a live feed (Unless there is a fuse box problem that is but that doesn’t seem to be especially common)
 
I found these quite helpful when asking the 'are all cylinders firing?' question:
http://www.halfords.com/workshop-tools/tools/hand-tools/laser-ht-lead-ignition-spark-tester?

And it's probably a red herring, but I once had a similar sounding starting problem, definitely had fuel and spark, but turned out to be the DME coolant temperature sensor. This was failing intermittently, causing not enough fuel on cold startup.
If you hold the throttle open on startup does it make any difference?
 
I had the same problem on my 924, it turned out to be dirt in the filter of the WUR, I don't know if the 944 has the same K Jetronic system but if it has then take out your WUR, carefully remove the filter and replace with very fine stainless steel mesh. Don't dismantle the WAR as they can be tricky to reassemble and take care that no dirt gets inside. Also check the fuel pressures at the fuel distributer, the correct readings should be in the manual.
 
Thanks everyone for your reply’s and help I will try everything that’s been suggested, I’m not in good health but soon I can I will get to work on it, ive got it over a year now and not got a drive in it yet ??????
 

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