Hi All,
I recently picked up a very clean RX300 with a known engine running issue. It was an impulse purchase as it was only $400. It is a clean Colorado car with no rust and very well cared for although the mileage is high at 230k miles. My thought was that for the price I could afford to take the loss if I can't figure out the issue.
The engine starts right up hot or cold, at idle it sounds great. It runs great until it reaches operating temperature. Then it bogs down, it will slowly crawl at idle but is mostly unresponsive to throttle input, and shifting seems rough. If I floor the gas pedal it will accelerate strongly, but as soon as you let off the gas it bogs down and slows to a crawl. Driving it is a balance between flooring it, slowing down and flooring it again. The seller told me that his mechanic said it needed a computer. He had replaced both A/F sensors, and the MAF sensor.
I pulled the following codes:
Pending:
P0172 Too rich bank 1
P1150 A/F sensor bank 2 sensor 1

Not Pending:
P0330 Knock sensor bank 2
P1130 A/F sensor bank 1 sensor 1

After reading through the forums, I tried the knock sensor hack. I cut the bank 2 wire and connected it to the bank 1 and the knock sensor code went away. It seemed to run better when cold than before, but the problem came back at operating temp.
I have seen a few places that will repair your engine computer. I find it hard to believe that the computer could go bad, but maybe its worth a shot? has anybody experienced a similar situation?
Thanks in advance.

 

Unless you're confident that both air fuel sensors were replaced with OE/Denso parts, I would replace with Denso and see what happens.