qoncept944

Recap.. My car won't start in the morning. It turns of and turns over but won't fire. Come back at lunch and it starts up fine for the rest of the day.

I've replaced the plugs and coil. Fuel filter is on the way, but I have a feeling it's not going to fix anything. Biggest problem is that I can only test it in the morning when I don't have time.

This morning, I pulled the cover off the DME relay and tried Sid's paper trick. With the switches thrown, I can hear the fuel pump. With the car in the on position but not running, I should also hear this, no? I tried it, didn't hear the fuel pump. Soo... bad DME relay? I hope?

qoncept944

bumpity

Kevin Baker

Check two things, on the AFM, there is a temp. sensor, which tells the DME to richen the mix, and advance the spark. Check, and I'm not sure of the correct name, the idle air control valve, under the intake runners. Do an archive search for a web page that details checking the temp sender for the AFM. HTH

Tom Carson

you by-passed the relay to force the fuel pump to run even when the motor isn't turning...

since it did not start you can assume it is not the relay...else it would have started when you by-passed it

the web page Kevin is trying to remember is:

<a href="http://www.frwilk.com/944dme/afm.htm" target="_blank">http://www.frwilk.com/944dme/afm.htm</a>

near the bottom is a test method for the AFM's temp sensor

btw...are you getting any spark when this thing won't start?

qoncept944

Tom, I'm not sure if I'm getting any spark. To check I'd have to try starting in the dark and see sparks arcing to the block, right? It starts until about 5am, which is when the sun rises (not to mention how hard it would be to find someone to get up at that time and try starting it while I watched it).

To check the relay this morning I used the paper trick to be sure the fuel pump was running, still wouldn't start. I've got a fuel filter I'll put in as soon as I can get in a garage, but I'm not very hopefull. I'll read up on the AFM today, and test it if I can do it out of the garage.

Thanks a bunch, guyys

Tom Carson

most auto parts stores have a cheap spark tester with instructions...it's easy & safe

yeah, the other way (even cheaper) is to "see sparks arcing to the block" by pulling the middle high voltage lead out of the distributor and holding it about 1/8" away from the metal while someone cranks the motor...just be careful you don't let it arc to any nearby wires or you could damage something