I'm getting code 52 on my 1990 4runner. I know that this is for the knock sensor but I was wondering if any other problems could cause it to come on that I should check into? Only symptom of any problem is poor throttle response when cold. It will rev up, but you cannot give it a quick shot of gas without some hesitation. After running for a few minutes and warm it is absolutely perfect.
I tried putting a '95 ECU in it that I have lying around and it gives me code 52 AND 27. Code 27 isn't even listed in my haynes manual but searching the internet it's supposed to be "sub-oxgen sensor" California only???? I have a Canadian model though so I don't know what gives. Maybe you can't use a "95 ECU in a '90? Thanks in advance for any help here.