The TPS is the key to your lump idle.>
Originally Posted by
Randell
what resistance values should i expect from the throttle position sensor on an M30 auto? The bentley doesn't give expected figures for this engine so i'm not sure if what i'm reading is showing a problem or not.
I'm getting a steady 11v on the harness end for both idle and wot terminals, but on the TPS end i get some pretty random resistance figures... at closed throttle i get between 2.5 and 11.5 ohms on pins 4 and 6, and at WOT i get resistance anywhere between 8 and 85 ohms on 4 and 5. it's steady, but the numbers change every time i test it. Is this why the bentley doesn't list the figures?
Opening the throttle at all gives 0 ohms on 4 and 6, and letting off from WOT gives 0 ohms on 4 and 5. To me this seems like it's functioning normally, but can someone please confirm? I want to rule this out of my lumpy idle diagnosis and move onto something else
thanks
When the TPS is closed you should have zero ohms (100% continuity) between 4 and 6. Same for 4 & 5 at WOT. Anything in between closed and open should be an open circuit. 2 yrs ago i was getting 2-5 ohms at closed throttle and my idle was terrible. I took the TPS apart (pretty delicate work) and cleaned the micro switch so my closed throttle resistance was zero and she idled perfectly.
Good luck.
Jeff in MN
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