Porsche Enthusiasts Club Forum

So I have a new development, while testing resistance on the grounds to the ECU I found that resistance is normal with ignition off,but increases when I turn on the ignition, is this correct?

My theory is this may be effecting my random spark issue.

YouTube video showing my test

https://youtu.be/i6O6xSRT6B8

[update - This is correct behavior as i have since repeated the test on my working 944 and it does the same]

Hi, I am having similar problems. Will check my car tomorrow and see if it’s the same as the video.

I checked mine and there was no change
My car is a no start thou so cannot guarantee they are right.

What would be really good if someone on the forum could post all the readings on the connector in both conditions from a known good car. Resistance and voltages so that it could be used for reference in these no start conditions.

All the ecu grounds end up at the bulkhead earth strap. Although I have not had a no start situation, I have had intermittant misfires especially if the battery has not been fully charged. Cleaning the bulkhead and block connections appears to have cured it. A friends 964 had bad starts, backfires and rough running, eventually the backfire blew off the inlet manifold, cause was a perforated FPR diaphragm.