Vehicles with certain V6 engines may illuminate the Check Engine Light one or more of the following codes: P0011, P0014, P0021, P0024, P0341, P0346, P0336, or P0391. Our technicians tell us that some vehicles may require a powertrain control module (PCM) software update to correct this issue. Other vehicles may have excess camshaft end play on one or both cylinder heads which will need to be corrected using special procedures outlined by GM.
The Check Engine Light With Code: P0011, P0014, P0021, P0024, P0341, P0346, P0336, and/or P0391 on Pontiac G8
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check engine light came on. code p0021 shows. car still run great so hope its an easy fix.
Engine Light came on, had diagnostics checked with code coming up p0021
The check engine light comes on, followed by the reduced power indicator. I've already had it at the dealer once, and it's there again right now. I don't know what they'll do this time. The first time it was a computer problem.