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Q: Misfire under acceleration

asked by on

Changed plugs and coils worked for 5 mins than Miss came back

My car has 95 miles.
My car has an automatic transmission.

First I would revisit the plugs and coils. there is always the possibility that something didn’t hook up properly. Pay close attention to the ground wires. They are the brown wires that emerge from the harness at seeming random places and bolt to the engine. There should be one or two on the cam cover. A loose ground wire can cause all kinds of problems. If all that is OK, it’s possible you are looking at an ignition module. That is an electronic module that is about half the size of a pack of cigaretts that lives in the right side of the engine compartment bolted to the inner fender or maybe the air cleaner. The ignition module provides the primary voltage for the ignition coils and they are a common failure for that car. The modules are pretty expensive though, so I don’t recommend just replacing it without a proper diagnosis. YourMechanic can send a technician to your home to check out your car’s misfiring issue and recommend a fix.

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