Q: check engine lit p0300,304,302,306 replace plugs and moved cops to diffirent postions still getting same codes.Change all injector

asked by on September 12, 2017

check engine lit. p0300,p0304,po302,p0306 replaced all spark plugs and removed COP to different position installed new injectors. Still getting p0300 and p0304,p0306,p0302

My car has 122000 miles.
My car has an automatic transmission.

I believe all of these cylinders are on the same Bank of the engine. With this in consideration the most likely cause after replacing all of those parts would be a vacuum leak on the intake manifold near that side of the engine. I would recommend having your vehicle smoke tested to determine if smoke comes out of the intake manifold in that area. If so check for cracks in the intake manifold. If no cracks exist simply replace the gasket.

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