Car will not run properly have to unplug VANOS to get it to stop misfiring. This is a steady misfire on cylinder 2 and multiple misfires on 1 and 3. P0300 and P0302. All new spark plugs, coils, new cam sensors and VANOS solenoids. Checked wiring ok. This is a brand new cylinder head. Timing chain is original did not replace but did replace chain tensioner. Installed with a local mechanic. If I unplug either VANOS sensor car runs fine expect when cold start. Could this happen if the timing chain was off and the adjustment is outside sensor range?
My car has 69000 miles.
My car has an automatic transmission.
Hi there. It is possible that the timing chain is the source of this problem. The two error codes P0300 and P0302 typically indicate a random misfire or misfire for cylinder 2 (the P0302 code specifically). However, it’s also possible that the lack of new tensioner is creating an issue as well. I’m rather baffled why you needed to replace the cylinder head with only 69,000 miles, but if it was due to an overheating problem, then it is more likely that you have an electrical wiring harness malfunction; if the vehicle actually overheated. Not sure what advice to offer you since there are multiple variables we simply don’t know. You might want to have a different mechanic try to resolve this issue.
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