P1135 Code -- 2002 Toyota Highlander 3.0L V6 engine

Question

The Highlander runs fine with 251,000 miles on the clock: but has been throwing the P1135 code from the OBDII system. The very costly fuel-air mixture sensor (over $400) was replaced last year - so I am assuming there is a bad sensor somewhere else. The vehicle is getting the same fuel economy as it always has.

Thanks!

Answer 1

$400 is very high, was that at the dealer?

The orginal Denso part is $125 or so online and labor is probably less than $40.

you can check/replace the relay

and test the senor

 

 

you can also check the wiring and the ECM