Q: Rough idle and there is a raw fuel smell coming from the exhaust.

asked by on February 28, 2017

A couple months ago, I saw a slight leak at the top of fuel injector #1, so I pulled the injector and replaced the o-rings. That stopped the leak but approximately 10 miles into my drive, the car started idling rough and there was a raw fuel smell coming from the exhaust. In wide open throttle, there isn't an cylinder misfire, but during minimal acceleration and while stopped, there is definitely a cylinder misfire. I've tried scanning the computer, but I keep getting an error message from my scanner. Do you think the fuel injector I replaced the o-rings on, could be blocked / clogged? How could I go about diagnosing that. Oh yeah, I also replaced all of the spark plugs and wires just in case, but that didn't help.

My car has 210000 miles.
My car has a manual transmission.

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If the spark plugs were replaced and there is too much fuel in the exhaust system, then the injectors are leaking and not spraying (atomizing) the fuel properly. A leaking fuel o-ring will make the fuel puddle up outside of the injector and give a fuel smell under the hood. I recommend flushing the fuel system with a fuel injection cleaner. If you need further assistance with your engine idle being rough, then seek out a professional, such as one from Your Mechanic, to help you.

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