Q: I am having a issue with my car. I have replaced timing, camshaft, spark plugs, valve cover gasket and I keep getting random miss

asked by on September 27, 2017

Hello, I have tried everything. I have replaced timing, camshaft, valve cover gasket and spark plugs. I keep getting random misfire. I took it to another mechanic he hooked it up to a machine and said that cylinder 1 was misfiring the most and that 3 would misfire sometimes with 2 and 4 not at all. I have spent a great deal of money just trying to see what is wrong with this car so maybe I can get it fixed.

My car has 157000 miles.
My car has an automatic transmission.

You may have ignition coils that are giving out a weak spark and or failing intermittently causing the misfire. Also a system that is running lean may cause random misfires. have the coils checked for spark output after engine is warmed up since they will fail more when hot. Also check and clean mass air sensor and throttle body and injectors. Then check fuel pressure is not low and replace fuel pump and filter if it is.

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