Car won't start when hot - just turns-over.

Car won't start when hot - just turns-over.

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HeWhoDaresRoy

Original Poster:

495 posts

216 months

Tuesday 4th September 2018
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It's a 1993 4.3 and I've changed the coil, ignition amp and ECU temp sensor, but to no avail.

The starter motor spins freely, but the car won't start unless I put my foot flat on the accelerator.

I don't suppose anyone can think of anything else to check? I'm out of ideas!

HeWhoDaresRoy

Original Poster:

495 posts

216 months

Wednesday 5th September 2018
quotequote all
Great stuff, thanks.

Stepper motor is new, so hopefully not that.

I've got Rovergauge cable and a multi-meter, so will see how far that takes me!

HeWhoDaresRoy

Original Poster:

495 posts

216 months

Friday 7th September 2018
quotequote all
OK, I got the car nice and hot (about 93c on the roverguage display) and sure enough, it wouldn't start.

The fuel temp said 35c, so not sure if that's warm or not. I also tested the output of the air mass meter as per this:

https://www.pistonheads.com/gassing/topic.asp?h=0&...

and it seemed ok.

No plug extenders on the car - just some sock things.

May I ask how to test voltage at the coil? I just had a bash and the multi-meter read 3ish volts on cranking, but as the car has cooled down a bit, it started right up! I was expecting 12ish volts, so guess I did it wrong....

HeWhoDaresRoy

Original Poster:

495 posts

216 months

Thursday 6th December 2018
quotequote all
Late reply, but....I checked voltage at coil and that seemed fine.

Found that the car starts when hot, but only when you turn the ignition on 4-5 times to prime the fuel pump multiple times. Does that sound like a fuel pressure issue? If so, I can't understand why it would only manifest itself when hot?

HeWhoDaresRoy

Original Poster:

495 posts

216 months

Monday 10th December 2018
quotequote all
Awesome, many thanks for taking the time to post that-up.

Car is now with local classics garage, as I don't have skills/equipment for testing fuel pressure, so will pass this info on to them.

Hopefully, we'll get it sorted soon.