NEW ISSUE!! TPS help needed. '94 2.3l

[iank1]

OK, '94 2.3l 5 speed, no AC, California emissions.

So I've been chasing down all these damn CEL issues, One MIGHT have been caused by a heater hose laying across the air charge/temp sensor. I'll update on that later.

Today I decided to test the TPS signals. OK, as follows, the main voltage signal, 5.0 volts on the nose. perfect. Sweep voltage, even and smooth, even while banging on it. Ground signal 12.0 volts, perfect. LOW IDLE VOLTAGE (here's the AHA! moment) When the idle screw is set to a reasonably low idle, engine hot, the voltage is .3 (!?!?) instead of .9 volts. Hence, code 121. SO with my multi-meter hooked up I turned the screw up until I hit .9 and VOILA! no more codes.... PROBLEM: now the hot idle is something like 1500 RPM. I can't turn the screw back down since I'll get the code again, it's like I need to twist the TPS on it's mount (or get a better quality one?) any pointers?

THANKS!

 

[RonD]

Never adjusted a 2.3l TPS but the ones I have done could be rotated slightly by loosening the two screws, if not I would drill out the plastic a bit so it can be.
The set screw should be set so warm engine idle is about 550rpm, IAC valve needs to be unplugged(closed) for this adjustment

And TPS at .7-.9vDC throttle closed, as you said.
I think .6vDC and under is when the code shows up.

 

[iank1]

AHA, that would help. I can split the difference by cranking down the screw to say, .8, then see if i can twist the TPS itself. OK, NOW WERE GETTING SOMEWHERE!!!

-Ian