Replacement O2 Sensor(Upstream)?
Thread Starter
Instructor
Joined: Nov 2018
Posts: 126
Likes: 6
From: Boalsburg PA
Replacement O2 Sensor(Upstream)?
We haven't narrow it down to faulty O2 Sensor yet, but just in case,
Denso makes direct fit one
https://shop.advanceautoparts.com/p/...012/20475268-P
But Im hoping to replace it with ACDelco unit if I can find it. Does anyone have part number or UPC# of ACDelco o2 sensor for upstream for 1995 Corvette base with LT1 with Auto??
Edit:
Is this the right one?
https://shop.advanceautoparts.com/p/...=ACDelco+AFS75
Denso makes direct fit one
https://shop.advanceautoparts.com/p/...012/20475268-P
But Im hoping to replace it with ACDelco unit if I can find it. Does anyone have part number or UPC# of ACDelco o2 sensor for upstream for 1995 Corvette base with LT1 with Auto??
Edit:
Is this the right one?
https://shop.advanceautoparts.com/p/...=ACDelco+AFS75
Last edited by Mity2; Apr 22, 2019 at 07:02 PM.
Racer
Joined: Feb 2019
Posts: 397
Likes: 29
From: Jackson, mi
the ac delco one also says, before cats. i am sure its the right one unless you have 6 O2 sensors, never heard of 6 but who knows. you have before, to measure the gases before the cat and after to measure how well the cat is working.
fyi, just because the code says O2 sensor, does not always mean that is the problem.. pretty sure there is a way to actually test an oxygen sensor. i have seen them when i changed the stock exhaust where they go off all the time triggering a code. my z 71 truck has done it ever since i put the flow master exhaust on it i think it flows so much better that the cats don't have time to do anything, maybe.. buy aspark plug defouler and install it in the O2 sensor hole then put the o2 sensor into that.. thats a trick to shut those pesky sensors up
fyi, just because the code says O2 sensor, does not always mean that is the problem.. pretty sure there is a way to actually test an oxygen sensor. i have seen them when i changed the stock exhaust where they go off all the time triggering a code. my z 71 truck has done it ever since i put the flow master exhaust on it i think it flows so much better that the cats don't have time to do anything, maybe.. buy aspark plug defouler and install it in the O2 sensor hole then put the o2 sensor into that.. thats a trick to shut those pesky sensors up
Last edited by bud40oz; Apr 22, 2019 at 07:11 PM.
Thread Starter
Instructor
Joined: Nov 2018
Posts: 126
Likes: 6
From: Boalsburg PA
the ac delco one also says, before cats. i am sure its the right one unless you have 6 O2 sensors, never heard of 6 but who knows. you have before, to measure the gases before the cat and after to measure how well the cat is working.
fyi, just because the code says O2 sensor, does not always mean that is the problem.. pretty sure there is a way to actually test an oxygen sensor. i have seen them when i changed the stock exhaust where they go off all the time triggering a code. my z 71 truck has done it ever since i put the flow master exhaust on it i think it flows so much better that the cats don't have time to do anything, maybe.. buy aspark plug defouler and install it in the O2 sensor hole then put the o2 sensor into that.. thats a trick to shut those pesky sensors up
fyi, just because the code says O2 sensor, does not always mean that is the problem.. pretty sure there is a way to actually test an oxygen sensor. i have seen them when i changed the stock exhaust where they go off all the time triggering a code. my z 71 truck has done it ever since i put the flow master exhaust on it i think it flows so much better that the cats don't have time to do anything, maybe.. buy aspark plug defouler and install it in the O2 sensor hole then put the o2 sensor into that.. thats a trick to shut those pesky sensors up
So far, passenger side upstream one is reading 4mV at key on. And seems that it should be any less then a 10mV. Once car starts, number jumps all over at idle. But that’s as far as I got today.
i clear the code, but does seems to start to miss when you put load on the engine(full throttle) past Around 3500rpm, and gets worse as rpm clime...
i had something similar with my wife’s old 93 Z28 with LT1 when it’s optispark started to die...
but seems that my car isn’t throwing any code related to that..
truth be told, I’m hoping it’s O2 acting up. At least they are cheap and easy enough to replace...
Le Mans Master
Joined: Aug 2015
Posts: 6,102
Likes: 1,981
From: St. Charles MO
You can test the O2 by logging the air:fuel ratios as you drive. Really, O2 sensors do get old and die - they should be considered wear items. And they are cheap. I wouldn't pour a bunch of time and energy in diagnosing them if these are originals. I'd replace the upstream ones as a matter of preventative maintenance. Densos are good, I think the AC Delcos are probably now made in China and no better than any cheap junk. Bosch doesn't have a good reputation either. I have an acquaintance who is a real GM electrical system guru, and he like Denso or NGK.
