Fuel leaks into oil and runs rough

1995 FORD RANGER
150,000 MILES • 4.0L • V6 • 2WD • AUTOMATIC
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CRAZYCLARK1972
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  • 1 POST
We have replaced pretty much all sensors, plugs, wires, coils. However, it still has a rough idle, and leaks gas into the oil and out of the tail pipe. Please help.
Jul 2, 2022 at 4:04 PM
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JACOBANDNICKOLAS
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Hi,

For this to happen, chances are you either have a cylinder that isn't firing and burning the fuel, excessive fuel pressure forcing too much fuel into the engine or a faulty coolant temperature sensor. Something is preventing the fuel from being burned in the combustion chamber.

Have you checked for diagnostic trouble codes to determine if the issue is specific to one or more cylinders? Also, have you checked things like fuel pressure and spark plugs to make sure they are in good condition?

If you haven't, start by testing fuel pressure to confirm it is within the manufacturer's specifications. Here is a link that shows in general how it's done:

https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator

I attached directions below specific to this vehicle. Also, the fuel pressure values are included.

Do this and let me know the results. You will need a fuel pressure gauge, but if you don't have one, often times a parts store will lend one to you.

Take care and let me know the results.

Joe

See pic below.
Jul 2, 2022 at 11:42 PM