Fouling an o2 Sensor (again)?
06-06-2009, 04:30 PM
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Fouling an o2 Sensor (again)?
I was having some troubles with my v8 recently. My mpg dropped to about 12, and my when I held the gas steady around 50+ the engine would buck and stumble.
I have another parts audi that runs perfectly, so I stole its o2 sensor and swapped it with mine. Just a temporary fix until my new one arrives from autohauz. When I replaced it my mileage went back up to around 19, and cruised perfectly.
My mileage is still great, but my car is starting to stumble again when I hold the gas steady at 50. Is there something wrong that is causing my car to foul these sensors??
I have another parts audi that runs perfectly, so I stole its o2 sensor and swapped it with mine. Just a temporary fix until my new one arrives from autohauz. When I replaced it my mileage went back up to around 19, and cruised perfectly.
My mileage is still great, but my car is starting to stumble again when I hold the gas steady at 50. Is there something wrong that is causing my car to foul these sensors??
06-06-2009, 06:20 PM
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Have you changed the fuel pressure regulator?
Have you cleaned the Idle Stabilization Valve?
How old are your electric bits, like distributor rotors, caps, wires and spark plugs?
Have you cleaned the Idle Stabilization Valve?
How old are your electric bits, like distributor rotors, caps, wires and spark plugs?
06-07-2009, 06:39 AM
#5
I'm beginning to think I have a FPR issue, my 2.5 YO says "Daddy car stinky"... That's after putting in the 4-wire O2. ISV does need cleaned/replaced, but that shouldn't cause the car to be overly rich.
06-07-2009, 07:44 AM
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The FPR (item 3) gets hose-clamped to a hose that frequently gets overlooked when the FPR is replaced. That hose can deteriorate and begin to leak a little fuel.
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06-07-2009, 12:10 PM
#9
Probably need the FPR and hose, because on hard acceleration I get a fuel smell in the cabin. I vaguely remember Ron mentioning that issue a while back, but duh, makes sense, if the diaphragm has an issue (rupture, whatever) you'll get fuel into the intake from the vacuum port, and if you have a bad hose, you'll have a gas smell...
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