1992 Lexus SC 300 code 71

SHANNON WOOLSEY

MEMBER
1992 LEXUS SC 300
3.0L
6 CYL
RWD
AUTOMATIC
117,000 MILES

Here recently I did the head on this engine and code 71 keeps coming back. I researched and checked everything in the egr system. Nothing broken or clogged and all parts are working? Now let me ask the question? This car is a Japan model not US (Cal, ) it doesn't have the exhaust temp sensor. I had to get a ECU for the car also, so I'm wondering if that ECU is for a California model and the computer can"t read the exhaust temp sensor there for code 71?

1 Reply

HMAC300

MECHANIC
48,601 POSTS

The temp sensor is probably an O2 sensor so if it's not there then it can't read it and the computer if it's California or federal will look for it. If the computer is not modified to not read that then it's going to look for it and not find. It cold be ashort between O2 and ecu if you have one hooked up. Of course there still cold be something wrong with engine like to much oil getting through to burn. So check pcv system as well for soft hoses and valve working.

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