drivers side 02 sensor (before the cat) just replace it, there like $65
Three years running. when the gas tank sees about 60F, check engine light
- Thread starter drvrd
- Start date
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Update on situation, replaced the fuel filter, and both upstream O2 analyzers yesterday. Disconnected to clear code but OBD still showing a PO135 (O2 analyzer)on bank 1 listed second to a PO300 ignition missfiring, then a PO178 flex fuel switch failure.
Since last posting and post these parts changes it has been hard to get started on first key turn.
Never saw water or crud drain out of the old filter. Filter was a Fram so it had been changed before 113k miles, today she has 214K on the clock.
those codes wont clear by simply disconnecting the battery, they will need to be cleared with a scanner, they "might" clear on there own after *** amount of restarts with a pass on each run, the flex fuel and misfire will most likely be unrelated to the 02 sensor code.
Ps to all, I had tried a $24 CatCarbon treatment with no relief of check engine light. However the replacing both upstream O2 sensors has not extinguished the check engine light and three codes described in the last post are still showing.
Thanks for your thoughts, if *** restarts can clear codes, how do I know when the reset happens? Does an INNOVA 5300 scanner clear the prior codes before reporting?
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The scanner will not erase the codes unless you tell it to, the 02 sensor should pass or fail at or within 50 miles of normal driving, if you clear the 02 code and it comes back then you might have a voltage problem on the harness or bad out of the box 02 sensor oem is best choice (or worse case scenario a bad cat). misfire could come back quickly if the problem is severe enough, not sure on the flex fuel sensor I have read they go bad and are not real hard to replace, otherwise not sure what the pass/fail data is on them.
Went back to O'Reilly and erased the codes. No codes came up after the erasure. Have restarted three time since and the check engine has not reignited. Weather today was in the high 60's. Will advise if the check engine re-ignites at lower temperatures.
Seems to be starting a bit better.
Thanks for everyone's help.
Seems to be starting a bit better.
Thanks for everyone's help.
An update, replaced the flex fuel filter, and both upstream o2 sensors. Cleared the codes and still see PO178 which is the flex fuel sensor switch low voltage. Truck is getting harder to start unless I prime switch 2-3 cycles before hitting the starter. Tried to measure fuel pressure but the rented brand new rig leaked fuel at the pressure relief valve..
Will check the pressure regulator, but suspect 225k fuel pump is failing. Is the flex fuel pump different from a regular fuel pump?
Will check the pressure regulator, but suspect 225k fuel pump is failing. Is the flex fuel pump different from a regular fuel pump?
Yes, the FF pump is different from the non-FF. Don't cheap out on the pump if you replace it; use OE. ACDelco MU2294 is the GOLD version.
Keep at that fuel pressure test -- that will tell you a lot.
Are you going to investigate the P0178 issue for the FF sensor?
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If you got 235 k out of the original fuel pump consider yourself lucky. If nothing else I would replace it as a maintenance item before it goes out and leaves you stranded.
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