Porsche Enthusiasts Club Forum

Hi

My 924 (1982 2.0 na) has had random moments dropping residual pressure when hot over the 2 years of ownership so last month I took the hit and replaced the accumulator resulting in great residual pressure in excess of the recommendations. Cold starts are perfect and it'll start up with no pushing of the accelerator pedal and settle to a nice even tick over. Driving is also fine but in the last 2 weeks its played up in hot start scenarios.

If I start the car and let it warm up (fan cutting in temps) then switch it off for 15 minutes it won’t start until totally cooled down so after some investigation I found:

- residual pressure is still fine along with system, cold and hot pressures + WUR is clean
- no spark from the coil (took a spark lead & plug direct from the coil) when the cars hot and won’t start
- no fuel coming through
- occasionally it’ll start before 100% cooled down but will cut out\die if left to run = back to waiting for it to cool down

I have power at the +ve of the coil and at the ignition module and also replaced both. If I jump the fuel pump relay the pump primes but I understand as a safety cut-out if there’s no spark the fuel pump relay wont activate. I think the core reason is lack of spark

All earths are clean and the battery is in good health. I've pulled the fuse board down but can’t find any traces of burnt wires or bad connections.

My last thought is the hall sender failing in the distributor or an electrical point failing but before spending any more money I wanted to see if anyone has any ideas??

As said from cold it behaves 100% and this only started since shortly after replacing the accumulator but I don’t quite see how this can be related?

thanks
Russell

Faulty coil is my guess, going open circuit when it gets hot.

That was my first thought and for £20 I gave it go but still lack of spark when hot. I also picked up a spare ignition module but this also made no difference so I'm thinking the hall sender in the dizzy is the only thing left!! If anyone has a spare please let me know.

I've gone through the wiring and pulled the fuse board done to clean it but didn't find any indication of burnt cables or damage.