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Re: P0121. Never duplicated here
Posted to Technical Discussion Forum on 2/28/2008 8 Replies

This is a rationality code set when the PCM calculated TPS differs from actual. AFAIK, it uses MAP & RPM as a reference.

Seeing as how it's a 3.8K, I'd be looking closely at the PCV cavity for a damaged valve O-ring or aftermarket PCV valve. A bum MAP sensor... Login to read more.

8 Replies Received (View Replies)