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Q: The 3rd and 4th cylinder are fouling the spark plugs. What could be the problem?

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I believe my truck is misfiring in the 3rd and 4th cylinders. I bought new spark plugs it helped for a while then it stared putting and bogging after about a week or two. I think it might be the distributor but i dont know. What do you think is the problem?
My car has a manual transmission.

A: Hello there, it sounds like you have severa...

Hello there, it sounds like you have several different issues going on with your 1989 Chevrolet S10. You did great replacing the spark plugs to address the misfire issue as this commonly is the cause. If the problem persists or the plugs are fouled there could be a few other issues present such as a valve cover leak onto the spark plugs, plug wires, cap & rotor, vacuum leak, or a fuel injector.

To avoid any unnecessary repairs, a qualified technician, such as one from YourMechanic, will be able to diagnose your misfire issues and make any repairs required to resolve it. Best of luck.

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