924s idle sputters and dies. Sometimes.

[curtisr]

Somedays my '87 924s just doesn't want to fire. It will turn over without hesitation, the fuel pump works (jumpered to check this) and fuel pressure tests at ~35# Removed, tested and cleaned the injectors as well but none of these efforts appears to be the issue. Gas is fresh.

If I unhook and reconnect the reference and throttle sensors (and threaten to draw and quarter them) it usually starts. After about six disconnect/reconnect efforts today I was finally able to get going from a busy intersection today where I had just stalled (the light turned green and bingo she stalls)

I've checked them (more than once) with a multi-meter as per Clark's Garage and both are within spec. I have as yet still to pull them completely to inspect the sensor ends.

This problem seems to exist regardless of outside temperature (say from 50 to 80 degrees F).

What I'm wondering then if it is possible that the speed and reference sensor can work intermittently or not. And if that's not the problem, any and all suggestions are welcome. (And, yes, I have researched this but I think the possibility of intermittent working sensors is kinda new.)

Thanks in advance.

[88Silver924S]

When my DME relay went bad it gave me start, no start, die issues until I found out the problem. During relay necropsy one of the coils had a circular green copper corrosion stain. The point is it died kicking and screaming instead of sudden death. Probably not your problem but if you have a known good spare you could swap it in for awhile.

On other cars I have had carbon tracks on the inside of the distributor cap and on rotors, they can be devilish to discover. One of the hardest to discover was a carbon track "leak" inside the rotor. When I have had a problem like yours an easy "try" is to pull the coil wire to the distributor and make sure the coil wire tower on the distributor cap and the one on the coil is clean (no external carbon tracks).

I have never yet had sensor problems but from what I read it sounds like it is usually less about the sensors themselves and more about failing wires/connectors, but IDK.

Good luck.

[curtisr]

Thanks, 88 I'll have a look.