O2 Sensor after new Fuel Pump
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O2 Sensor after new Fuel Pump This is a low mile, all original, 1998 Camaro Z28 I picked up a little over 5 months ago. Only issue I had leading up to this was the failing fuel pump. I had it in for a full diagnostic, fluid flush, and belt replacement 3 months ago and the only thing they came back was the fuel pump.
Any idea why the O2 Sensor would be reading 0 Mv when driving after a fuel pump replacement? Prior to the install, there were no codes except a MAP sensor. New pump is a OEM style replacement from Summit (Delphi I think) and the install went without any issues. Fuel pressure seems fine, car cranks up instantly every time now. Except the O2 sensor is now throwing out code.
Trying to see if there are any common areas I should check before taking it back in to be diagnosed. $140/hour isn't a cheap way to find out it was an easy. Hoping someone here ahs run into this or might have some tips on where to look.
Thanks
Any idea why the O2 Sensor would be reading 0 Mv when driving after a fuel pump replacement? Prior to the install, there were no codes except a MAP sensor. New pump is a OEM style replacement from Summit (Delphi I think) and the install went without any issues. Fuel pressure seems fine, car cranks up instantly every time now. Except the O2 sensor is now throwing out code.
Trying to see if there are any common areas I should check before taking it back in to be diagnosed. $140/hour isn't a cheap way to find out it was an easy. Hoping someone here ahs run into this or might have some tips on where to look.
Thanks
Joined: Nov 2001
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From: Schiller Park, ILL Member: #317
Sounds like you either need a new O2 sensor, or there is a harness issue (the latter of which could also be contributing to the MAP code, but that's unlikely if the MAP code was present long before.)
I don't really see how the fuel pump would have any impact, they shouldn't have touched anything that would affect an O2 sensor or harness for such.
I don't really see how the fuel pump would have any impact, they shouldn't have touched anything that would affect an O2 sensor or harness for such.
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Sounds like you either need a new O2 sensor, or there is a harness issue (the latter of which could also be contributing to the MAP code, but that's unlikely if the MAP code was present long before.)
I don't really see how the fuel pump would have any impact, they shouldn't have touched anything that would affect an O2 sensor or harness for such.
I don't really see how the fuel pump would have any impact, they shouldn't have touched anything that would affect an O2 sensor or harness for such.
Thanks for the reply! Spoke to my guy and he says all 4 are throwing the code (I didn't realize there were 4).
Any thoughts to possible causes beyond the wiring harness? Is it even possible to check that? Maybe a grounding issue?
Joined: Nov 2001
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From: Schiller Park, ILL Member: #317
Very unlikely that all four (two pre cat, two post cat) O2 sensors would fail simultaneously so there is likely something else at the root, possibly a harness issue at or near the PCM. What exact codes are being triggered?
