Q: Carbon fouled #3 and computer shows misfire on #3

asked by on June 28, 2016

My car had a carbon fouled #3 plug and the computer showed a misfire on #3. I replaced the injector and plugs which solved the misfire and then there wasn’t anything showing on the computer. I began to get a lot of fumes from the exhaust and some light white smoke. In the tail pipe, there is some moisture. I had already performed a chemical test for a blown head gasket and that came back good. The fumes from the exhaust are getting inside the car when I’m driving on the interstate, especially if I’m passing a semi-truck. When I get the exhaust looked at, should they look for leaks or could the problem be something more than that?

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