chrislofty

Driving through the country, sun shining, all is good in the world. Suddenly accelerator seems to have no bearing on revs, warning lights come on and car drops into limp mode.


Took it to see a friend of a friend at Lexus who pulled this:

P0120 - throttle/pedal sensor/switch A circuit
P0141 - oxygen sensor heater circuit bank 1 sensor 2
P0155 - oxygen sensor heater circuit bank 2 sensor 1
P1120 - accelerator position sensor circuit
P1121 - accelerator position sensor range/performance problem


Cleared codes and only the O2 sensors codes came back.


Now, I'm torn between replacing the lamda sensors or looking into the fly-by-wire system as surely a bad O2 wouldn't cause the accelerator issue (pedal having no bearing over revs)?


Also if the revs are wavering and I pop the cruise control on its fine, so is this bypassing the pedal? Meaning its the signal from the pedal that is failing?

BossGS4

iTrader: (2)

Could be a failing VVTi Solenoid. same symptoms were happening on my '01 GS430 and found that my right bank VVti solenoid was failing.

There's info on it here in CL and order the TOYOTOA part to save some $$$

wbmx1981

When my MAF sensor went out it gave me a bunch of codes too, and it acted really weird. I thought my throttle body was going bad, but it turned out to be my MAF Sensor. You can force the car into "safe mode" by running it without the MAF sensor connected. Hopefully that helps you further diagnose your issue.

deepdish

A similar thing happened to me on my 2001 GS430. Pulled out of my driveway, then the engine died and 4 or 5 warning lights came on such as VSC OFF, etc. Then it happened again the next day. Got really nervous, but it ended up that my battery was dying. Replaced the battery and it didn't happen again.