Cutting Out When Hot

[Rascal]

Hi can anyone advise please ?

When im driving the car when the engine has warmed up after about 20 mins it just cuts out and wont start which is right dangerous when on motorways etc

The aa man the other week suggested it might be the fuel pump relay .....which i then replaced.

Took it out today for a spin and once again when it had warmed up engine just cut out and would not start again untill about 20 mins later once it had cooled down.

Someone suggested the coil or distributor ??

Thanks

[Rascal]

Yeah would help wouldn't it....1989 e30 2 door

[Rascal]

2.0 auto thanks

[Brianmoooore]

The trouble with using the flow chart to diagnose this particular problem is that the fault cures itself as things cool down, leading to a strong possibility of misleading results.
The problem you describe is what tends to happen when the crank position sensor begins to fail, so as a short cut to diagnosis, I suggest you remove the plug from the engine ECU, just under the RH side of the dash, identify pins 47 and 48, and connect an ohmmeter across them (don't force large meter probes into the plug buckets!). You should get a reading of about 540 ohms.
Now refit the plug, run the car until it cuts out, then quickly unplug it and measure the resistance again.

[Rascal]

The aa man said there was no spark

[Rascal]

Thanks had a look at the wiki and does help thankyou

[Rascal]

Report from aa reads: Engine cranking, no spark from coil, fuses ok, power to coil