Re: O2 Sensor question

[Dave Head <dhead@sundial.sundial.net>]

At 01:15 PM 12/18/96 -0700, you wrote:
>Dave,
>
>Hi. Hope this isn't ain intrustion but I had another question about my
>'875KTQW. I saw in one of the archives that you had been dealing with you
>O2 sensor back along the way. My mpg went down about 4-5 mpg in the last
>few months with no loss of performance and one fellow saaid it might be
>the O2 sensor.

Yer O2 sensor starts wearing out from day 1. What happens to it is that it
corrects more slowly to changes. Very hard to feel since it happens very
slowly. Mileage will slowly decrease. V8s and V6s see surging, but the I5
doesn't seem to exhibit it. Get a cheap dwell meter, hook it up to the test
connection on the freq valve and you can see how fast it swings to correct.
Test conn is two wires (brown/blue usually) going to a white plastic
connector flopping about unsecured in front of the windshield washer bottle,
outboard  of the frquency valve.

>Anyway, I was wondering if you concurred and how I could check mine - like
>where is it!? Also, I was wonsering if you went with a Bosch part or
>another generic?
>

I went with a non German Bosch part (South America), universal 3 wire -
about 50.00. The Bosch univ runs about 70.00, and the plug in part about
$130.00!
Location - look on exhaust manifold behind turbo directly across from air
filter - right on top. Easy to remove. Plug in is next to fuel distributor.
About the only way to check it is with a propane torch, outa the car, hooked
up to a digital multimeter. If you're over 60K, replace it.  With a short
wrench or proper socket (Pep Boys, AutoZone, etc) and a soldering gun itsa
30 minute job in the dark holding the flashlight in yer teeth. Don't get tha
antisieze supplied on anything but the threads, and make sure the manifold
is warm (alert!).
Also check all yer hoses in the car fer softness, cracks, etc. The Bosch
system can correct/mask them, but it can still affect mileage.

HTH

********************************AUDI FAN***********************************
                                       EMCM(SW) Dave Head  
87 5KCStq 182K miles and counting... 1.8 bar boost - Whee!
                                              Maitland, Florida
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