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Hint of fuel in air intake

779 Views 21 Replies 6 Participants Last post by  metalmike187
Good afternoon.

I was cleaning the airbox, snorkel and air guide along with changing the air filter and noticed a very slight smell of gas. A hint if you will. Could a failing fuel pressure regulator be the culprit?

I know if draws vacuum from the resonator box on top of the engine. I removed the box and there was no fuel in there, but it also had a slight aroma of fuel. I'm not getting a code and I haven't lost any fuel economy. I'm going to pull the line later and smell if it has a fuel smell. If I recall correctly, if it smells of fuel the diaphragm is leaking and the unit needs replacing?

What else might be causing the fuel smell? PCV system issues?

Thank you.
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does the system in question really just consist of the pedal, PCM and TB like the diagram in the Haynes manual?
...and the wire harness that connects 'em together.

But you've already got this solved, so that's not information you need now. Just keep in mind that wire harnesses are often "forgotten" components when doing diagnostic work.

Good job.

And, no love for Haynes/Chilton/Clymer manuals here, either. They're "simplified" to the point of being almost useless for anything beyond rudimentary work.
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Final Update:

Drove the 26 miles to work today going various speeds and with differing idles without issue. Shifts felt smoother, idle felt nicer, etc. (Although this could just be psychosomatic due to new parts being installed)

I also noticed a bit of a change in performance. I don't know how to word it right, but it's different. I don't want to call it a miss, as it wasn't a miss. Maybe a pulse? Not sure, but whatever it was is also no more. Also, no more "runaways" with the throttle feeling like it continues to apply even after letting off the pedal.

I think we can officially put this problem to bed and call it fixed.

Thank you all again for the well wishes, kind words and advice.
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