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Q: misfire in cylinder #1

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I've had this mis fire for a while now, even after replacing the spark plugs, spark plug wires, distributor cap, coil pack, and fuel injectors. And it will every once in a while idle ruff on the start or have issues not wanting to turn over, and some gas has to be given until it doesn't want to shut off.Also, every once and a while (once a week probably) it will shut off at a light or stop and sometimes while driving. It seems when the jeep warms up it runs better. Please help I don't know what else I can do to solve this. Thank you

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

It is possible that your number one cylinder could be misfiring due to low compression in that cylinder. I would recommend having a compression test performed by a qualified mechanic to determine if the piston rings are holding up to the compression that they are exposed to. The manufacturer releases a compression specification that this number will be compared against.

If the compression is low in the number one cylinder, the piston rings may be faulty and need replacement or the cylinder walls are far too worn down due to lack of lubrication and are no longer able to hold compression even with good rings. In this case, the engine block would likely need to be bored out slightly and replaced with larger pistons or a new engine would need to be installed.

At 200k miles, it is not uncommon for a cylinder to lose compression due to piston ring failure. Engine blocks being too worn out is an unlikely cause, but is still possible. I would also check your exhaust for white smoke. If you have white smoke coming from your tailpipe (even intermittently) this means your engine is burning oil and could be an indication that your compression in one of your cylinders could potentially be low.

I’d recommend having the vehicle checked out by a qualified mechanic who can diagnose your misfire firsthand to pinpoint the fault.

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