924S Won't Start
Discussion
I think I may have upset it!
I swapped the main instrument surround over, so had to unplug the rev counter etc before plugging back in. I have also tucked away a nest of wiring on the passenger side including a switch, presumably wired to the fuel pump. Perhaps I have disturbed something?
The PO removed an alarm/immobiliser, however I can still see remnants of it. I can also see a black box by the ECU on the driver side.
Now the car cranks, the fuel pump buzzes but it doesn't fire. I got a few splutters but it cuts out almost immediately. I have pulled the DME relay out, wriggled it around etc. The rev counter does bounce, but only a fraction. Could this be the route of my problem?
I can hear the fuel pump and I have a spark.
Jumpered the DME but this didn't make a difference, the fuel pump runs with the key turned to the first position anyway.
This is what I have under the passenger side:
Relays - Radio controlled black box - big red relay - u/s switch to fuel pump - mystery black switch that doesn't appear to do anything
Driver side ECU and this black box
I'm at a loss, the 2 litre 924's I'm used to were much simpler!
I swapped the main instrument surround over, so had to unplug the rev counter etc before plugging back in. I have also tucked away a nest of wiring on the passenger side including a switch, presumably wired to the fuel pump. Perhaps I have disturbed something?
The PO removed an alarm/immobiliser, however I can still see remnants of it. I can also see a black box by the ECU on the driver side.
Now the car cranks, the fuel pump buzzes but it doesn't fire. I got a few splutters but it cuts out almost immediately. I have pulled the DME relay out, wriggled it around etc. The rev counter does bounce, but only a fraction. Could this be the route of my problem?
I can hear the fuel pump and I have a spark.
Jumpered the DME but this didn't make a difference, the fuel pump runs with the key turned to the first position anyway.
This is what I have under the passenger side:
Relays - Radio controlled black box - big red relay - u/s switch to fuel pump - mystery black switch that doesn't appear to do anything
Driver side ECU and this black box
I'm at a loss, the 2 litre 924's I'm used to were much simpler!
The plot thickens...
With the key in position 2, I can hear the fuel pump running, however when I turn to crank it then it cuts out.
It should be the other way around. I swapped the ignition switch for a known good one - no difference. Jumping the DME relay doesn't make the fuel pump run either.
This suggests the wiring from the DME to the fuel pump is a problem, however it runs from the ignition switch?
With the key in position 2, I can hear the fuel pump running, however when I turn to crank it then it cuts out.
It should be the other way around. I swapped the ignition switch for a known good one - no difference. Jumping the DME relay doesn't make the fuel pump run either.
This suggests the wiring from the DME to the fuel pump is a problem, however it runs from the ignition switch?
I think it would be a huge coincidence that it has now stopped after unplugging the rev counter and just moving that wiring?
I have bought a multi meter and tested the DME relay socket & fuel pump fuse. I get 12v at the fuse.
With the relay, I get 12v constantly at pin 30. Pin 86 (ign) I get 0v with the key out, 12v with it in accessory position and 9v cranking.
I still can't jump the relay to get the pump to run.
I have bought a multi meter and tested the DME relay socket & fuel pump fuse. I get 12v at the fuse.
With the relay, I get 12v constantly at pin 30. Pin 86 (ign) I get 0v with the key out, 12v with it in accessory position and 9v cranking.
I still can't jump the relay to get the pump to run.
What he ^^^^ said. If it's gonna fail sometime, then it's gonna fail sometime. My ECU (early 84) failed near the end of a 100+ mile run; had been running perfectly until that moment. I'd definitely try a known working ECU if you can get hold of one. Very easy to swap ( as long as you have triple-jointed arms).
Your big red relay is the one for the electric windows.
The detritus left behind by alarm systems leads me to think that the guys who designed and fitted them should be shot.
Your big red relay is the one for the electric windows.
The detritus left behind by alarm systems leads me to think that the guys who designed and fitted them should be shot.
Edited by gothatway on Thursday 14th May 23:03
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