Another observation about O2 error intermittent

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matreyia
Posts: 64
Joined: Dec 22, 2021 1:05 AM
Location: Houston

Another observation about O2 error intermittent

Post by matreyia »

Hey Everyone,
I just observed/discovered something about intermittent O2 errors if you replaced the sensors, and can't find any other typical vacuum leak locations... I was scratching my head when suddenly the O2 double flash came up after replacing all my brackets and toothed bolts for the alternator, AC compressor, and the PS pump mounts. I rechecked all typical leak locations and found everything all air tight. Then the error went away for a day. Then it came back again...so I looked again, and something that I never thought about was out of place. It turns out the oil dipstick o ring was so loose the dipstick was dislodged and air was leaking from the dipstick.

I reinstalled full the dipstick and the O2 error went away. I never experienced a dipstick induced o2 sensor fault before during my 15 yrs of car work. Live and learn. So if you can't find any leaks in the typical weakpoints, then double check the dipstick to make sure it is sealed.
1st 5er
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Joined: Jun 13, 2008 12:15 AM
Location: Cypress
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Re: Another observation about O2 error intermittent

Post by 1st 5er »

:D
turbodan
Posts: 9153
Joined: Jan 09, 2007 10:19 PM

Re: Another observation about O2 error intermittent

Post by turbodan »

That will do it. The entire crankcase is maintained under a slight vacuum. Oil cap or dipstick will allow significant unmetered air intake.

I prefer this simple system to the newer, vastly more complex and unreliable systems with vacuum regulating diaphragms and a nest of hoses.
matreyia
Posts: 64
Joined: Dec 22, 2021 1:05 AM
Location: Houston

Re: Another observation about O2 error intermittent

Post by matreyia »

When I think about it would agree with Dan.
Hey Turbodan, you mind if I PM you about guidance on turbo charging this 528e?
turbodan
Posts: 9153
Joined: Jan 09, 2007 10:19 PM

Re: Another observation about O2 error intermittent

Post by turbodan »

matreyia wrote: Aug 10, 2022 8:42 AM When I think about it would agree with Dan.
Hey Turbodan, you mind if I PM you about guidance on turbo charging this 528e?
I'm available
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