Hello,

My 2002 Highlander is in the shop for a valve job. One burnt valve and one bent in the same cylinder. The engine is back together and runs on all cylinders again, BUT, I'm told it needs a new ECU.

My mechanic said it is in "limp home mode". He believes the problem is a bad ECU not responding to two of the O2 sensors. He ruled out the sensors themselves by plugging in a known good O2 sensor and saw no response.

My questions.

1. Is swapping out ECUs a simple task, or do you need the keys from the donor vehicle, etc? He said there is theft prevention enabled that may make things not so simple.
2. Does what I described make sense?

-Jason