Q: Misfire in 2 cylinders

asked by on October 09, 2016

The car has a misfire/knock not sure which. It has little power, the timing is fine, spark plugs are new, we have confirmed we have spark. There was oil underneath the spark plug cover. It also is getting fuel, and the fuel pump sounds fine. Confused on what it could be. Any help would be great.

My car has 200000 miles.
My car has an automatic transmission.

Hi, thanks for writing in. Was there oil down in the spark plug wells also? If so, the rubber plug boots may still have enough oil on them to short to the cylinder head. It is also possible, with your mileage, that you have a blown cylinder head gasket. Checking for low compression on 2 adjacent cylinders or checking for combustion gases in the engine coolant will be useful guidance. Some (but not all) ’95 Volvo 850s have OBD II diagnostics, many did not. Regardless, check for problem codes also (whether the Check Engine light is illuminated or not). Any codes that are set or pending will be a help in diagnosing this problem. If you would like help, consider having an expert automotive technician from YourMechanic come to your home or office to inspect and diagnose this issue for you, and make or suggest any repairs as needed.

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