Stopped at a red light and tach dropped to 0, and engine died. Started right back up, but wouldn't idle. Made it back to my shop by keeping the rpms up when stopped. Runsu just fine, just won't idle. Unplugged the tps and it idles fine. Plug it back in, and engine dies. Haven't got to look at it yet, wondered if anyone else has experienced this and what the cause was. 40 years, and this is a first.

I had mine suddenly run really crappy, turned out to be the MPS.

I would try cleaning the contact plate inside the TPS and then re-adjust it. Mine has given me issues before and that seems to take care of it.

Curt -

Someone on here in member vendors was making replacement TPS circuit boards for them, if yours looks worn at the contacts.

Cheers!
Tom
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I have a new board that has been adjusted. I'm just wondering what in the tps would make the car not idle. It seems a more likely cause would be the ecu not receiving a signal or not reading it correctly.

Haven't experienced this first hand Curt but read a thread where someone finally discovered the finger(s) were tweeked longitudinally. e.g. riding on their side. GL

Let or djet?

Vacuum leak on ljet will do this...like a rack in the big tube, or the oil cap seal or print is bad.

Vacuum leaks on ljet kill the motor at idle
Vacuum leaks on djet or carbs make high idle

The car will idle and run fairly well with the TPS unplugged .....................

The Cap'n

You are correct as usual Cap'n, but you already knew that.



I've been working out of town this week (retirement doesn't pay very well), but I'll get back to it saturday.

That is a bizarre one.....maybe a break in the wiring somewhere?? Weird!

I just got done with my yardwork this morning and headed to my shop shortly. I'll start with the tps part of the harness.

More to come.

Curt...you wouldn't happen to have a spare know good MPS?
my rebuilt one drove great, but idled badly; needed to adjust.

Got it fixed turned out to be the ecu. all is good now.

File a complaint, Curt. You were cheated. These things should last more than 40 yrs. don't ya think?

...I'm very curious these days...must be all the vacation/relaxation the past week.....so have to ask; How did the problem lead you to the ECU??? do tell, what was the process??????

Sorry Ray, it was mostly a process of elimination. Wiring checked good, tps adjusted to 0 ohms. Using brad anders chart I checked ohms at #17 wire on the ecu plug. He called for under .5 ohms. After dismantling a tps and sanding the gold on the board, then hand polishing it with jewellers rouge, it ohmed at .2. No change. It just had to be the ecu. Since I already had the plug off, it was simple to check.