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Q: Hydrolocking #7 cylinder

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5.3 had a bad temp sender and fuel pressure regulator when I bought the truck. When I replaced the pressure regulator ugly filth poured out so upon inspection fuel filter was replaced also. New plugs and wires were added and this brought her around and drove fine for about a week. It then set a 307 code so I pulled the plug to find it extremely flooded so I replaced the injector and my miss disappeared.I got about 4 days out of that injector and had to replace it again. Driveability returned and about 200 miles later I tried to start it. It cranked but stopped abruptly and would only engage starter and kick out. Pulled #7 plug only to find the same fuel soaked condition. Rotated and replaced plug and she runs but the miss returned. The motor is a little tired. I get 130lbs in each cylinder so I'm hopeing maybe you can point me in the right direction.

My car has 245000 miles.
My car has an automatic transmission.

Hello. If that cylinder has good compression and is getting spark then the cause would be due to the injector simply pouring too much fuel into the engine. If the injector is new then you more than likely have an electrical issue that is allowing too much fuel to enter that cylinder. This is usually due to the injector staying open for too long. I usually start by testing the circuit to see if this is the case. I can also use my scan tool to check the pulse width of that injector. If you need to have this misfire condition checked, consider YourMechanic, as a certified mechanic can come to your home or office to diagnose and repair this issue.

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