Intermittent throttle position & TPS voltage fluctuating

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tony-baroni
Posts: 10
Joined: Tue Mar 17, 2015 4:38 pm

Intermittent throttle position & TPS voltage fluctuating

Post by tony-baroni »

I continue to hunt for the cause of my intermittent high idle. This morning I hooked up the PC, and it was normal. I turned off the van..repeated the start, and lo and behold it occurred, while I was recording!

Basically the TPS voltage was fluctuating, between 0.3 and 0.6 with the key in ON position, throttle pedal fully UP. When the vehicle starts, then it became steady, but the throttle position was at 10% or so even though the pedal wasn't depressed at all. Stabbing the throttle doesn't fix this. The IAC counts goes way high, when it's normally very low.

It's a TBI engine from 95. I've replaced the TPS twice, and the connectors at the TPS as well. The problem occurs upon start intermittently, I havent found a pattern yet. There is no binding on the throttle plates or cable. I've had it to two mechanics, they can't find anything wrong...any suggestions for where else I might search for the problem?

I would add the log file, but haven't figured out how to do so yet.
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