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Check engine light indicates 3rd cylinder misfire. Seven auto shops and dozens of cans of sea foam, new spark plugs; wires and a coil cap. the light still comes on. Last week car stalled twice at 50mph all dash lights came on, then keep going like nothing ever happened. Only problem car ever had was an antifreeze leak which was fixed with a small elbow connection where the leak came from. The car did over heat one time where the engine light came on then car stopped on side of road. but once the elbow was replaced the car ran fine. Now engine light still comes on. The garages and dealership can't seem to find the problem because all the tests come back the car is fine. Do you have any ideas?

Answers from the Automotive Experts

Jessica Howe, Automotive Expert & Coach at


Thank you for writing in. Approaching your problem by starting with the spark plugs and ignition was a good call. It seems as though you have exhaustedly your efforts in this area, and may need to turn your attention to other components. Focus on the fuel system. Using that much sea foam in the fuel system isn't recommended, and it may have amplified the problem if it was fuel related. At this point, you are going to want to have the fuel system tested, starting with the fuel pressure. You will have to install a fuel pressure gauge, and try to get the vehicle to stall, so you can see what happens to the fuel pressure at that moment. You may also want to look into the EGR system, take a closer look at the throttle body, and check the electrical system powering the fuel pump. Only further testing will tell. Either way, you must be able to replicate the stalling issues while testing to find the culprit, which takes time. Good luck!

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