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Q: Misfire on cylinder one

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Hello I have a check engine light on for a misfire on cylinder one I recently had the coil pack replaced for a misfire on cylinders 1 and 4 check engine light turned off for about a week then turned back on for a cylinder misfire on cylinder 1. I checked te spark plugs and wires they were fine did a spark test came out fine. Checked injector pulsation as well as ohmed the injector out. I looked for vacuum leaks came to fine none as well as made sure the engine was receiving sufficient air. I'm also recieving another code now that I've pulled up the codes again for a fuel pressure regulator sensor. Could that be the problem causing the misfire?

My car has 180000 miles.
My car has an automatic transmission.

A misfire to cylinder 1 may be a fuel pressure regulator sensor problem but it is most likely due to a clogged injector on number one. You will need to scan and view data to see if fuel pressure sensor is needing replacement first. Then have the injectors cleansed to see if the codes go away.

I’d suggest you get this looked at by a qualified technician who can perform these checks to diagnose your Check Engine Light and make the appropriate repairs to your vehicle.

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