Hi all. New to the forum, but about to pull my hair out over problem.
2008 Corolla auto w/55,000 miles now
Problem began last winter at 47,000 miles. Check engine light/loss of throttle control/ Codes P2127 & P2138 related to throttle voltage. Happens when temp drops below 32-34 and then car begins warming up when I drive. After car gets warmer regain throttle control. Check eng light goes out after ignition switch cycles on/off a few times. No problems in warm temp (above 40).
Last winter local shop cleaned throttle body – no help
Replaced throttle pedal assy – no help
Told me next step was ECM
I disconnected battery and removed and reset connectors at ECM
Then came warm weather – no problems
This winter when problem returned drove 35 miles to Toyota dealer and told them history of problems and what I had tried and that I suspected ECM.
Trip 1 – checked – told me throttle body would fix - ordered new throttle body
Trip 2 – replaced throttle body – next cold spell same codes
Trip 3 – diagnosed bad throttle position sensor – ordered part
Trip 4 – turns out tps is part of throttle assy. And I told them no because it had already been replaced
Between trips I was able to keep problem from occurring by keeping cabin of car warm at home with a 120v space heater.
Trip 5 – back for diagnosis, but service writer was confused and had mechanic install throttle assy. – made them remove throttle assy. And talked to mechanic. He tapped on ECM and made the problem re-occur. Suspected bad solder joint in computer and ordered new ECM
Trip 6 – replace ECM (under warranty)
No problems for first 2 or 3 cold spells, but now same problem has returned. I suspect a pin in the wiring harness at the ECM, but which one.
thanks
Ed
2008 Corolla auto w/55,000 miles now
Problem began last winter at 47,000 miles. Check engine light/loss of throttle control/ Codes P2127 & P2138 related to throttle voltage. Happens when temp drops below 32-34 and then car begins warming up when I drive. After car gets warmer regain throttle control. Check eng light goes out after ignition switch cycles on/off a few times. No problems in warm temp (above 40).
Last winter local shop cleaned throttle body – no help
Replaced throttle pedal assy – no help
Told me next step was ECM
I disconnected battery and removed and reset connectors at ECM
Then came warm weather – no problems
This winter when problem returned drove 35 miles to Toyota dealer and told them history of problems and what I had tried and that I suspected ECM.
Trip 1 – checked – told me throttle body would fix - ordered new throttle body
Trip 2 – replaced throttle body – next cold spell same codes
Trip 3 – diagnosed bad throttle position sensor – ordered part
Trip 4 – turns out tps is part of throttle assy. And I told them no because it had already been replaced
Between trips I was able to keep problem from occurring by keeping cabin of car warm at home with a 120v space heater.
Trip 5 – back for diagnosis, but service writer was confused and had mechanic install throttle assy. – made them remove throttle assy. And talked to mechanic. He tapped on ECM and made the problem re-occur. Suspected bad solder joint in computer and ordered new ECM
Trip 6 – replace ECM (under warranty)
No problems for first 2 or 3 cold spells, but now same problem has returned. I suspect a pin in the wiring harness at the ECM, but which one.
thanks
Ed