O2 Sensor readin 0 mV
#1
O2 Sensor readin 0 mV
Should an oxygen sensor ever read 0 mV if it is heated up, even if the exhaust is super lean? I've been getting readings of 0 mV with the occasional 4 mV, even though the engine seems to be running okay. Looking at O2 sensor info on the net, it looks like the bottom should be more like 100 mV as long as the sensor is heated up.
I'm wondering if my sensor is bad. It doesn't always read 0 mV, but it does when the car is at open loop idle, and I can't seem to give it enough fuel to bring it up. Possibly a bad heater? I've got a 3-wire Bosch.
I'm wondering if my sensor is bad. It doesn't always read 0 mV, but it does when the car is at open loop idle, and I can't seem to give it enough fuel to bring it up. Possibly a bad heater? I've got a 3-wire Bosch.
#2
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Car: 91 GTA, 91 Formula, 89 TTA
Engine: all 225+ RWHP
Transmission: all OD
Axle/Gears: Always the good ones
Throw the bosch away and go buy a delco.
Bosch and 02 should not be used in the same sentence.
Replace it with the equivelant delco sensor :-)
Yes , super lean will indeed drive the 02 mv down to near zero.
In highway mode at 16-1 afr mine drops into the 2 digit range and low low 3 diogit area
later
Jeremy
Bosch and 02 should not be used in the same sentence.
Replace it with the equivelant delco sensor :-)
Yes , super lean will indeed drive the 02 mv down to near zero.
In highway mode at 16-1 afr mine drops into the 2 digit range and low low 3 diogit area
later
Jeremy
#3
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Car: An Ol Buick
Engine: Vsick
Transmission: Janis Tranny Yank Converter
Originally posted by 3.8TransAM
Bosch and 02 should not be used in the same sentence.
Bosch and 02 should not be used in the same sentence.
Doc's thinking he's heard that before,
Truer words, yada yada...
#4
Originally posted by 3.8TransAM
Bosch and 02 should not be used in the same sentence.
Bosch and 02 should not be used in the same sentence.
Yeah, I ordered a Delco, just waiting for it to show up....
#6
Just to update, I got my Delco AFS-74 installed and it did not solve my problem. It does seem to have a more subtle response than the Bosch, like it spends less time pegged one way or the other in closed loop, but it still eventually dropped to 0 mV on me at startup.
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Car: GTA -89
Engine: Blown 415"
Transmission: 4L80E
Axle/Gears: Strange 12-bolt
My friend has the same problem with his new engine..... His car switches between open/closed loop when he drives it no Error codes.......after a while his oxygen sensor hits 4mV and the BLM goes sky high.......
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#8
Originally posted by gta324
My friend has the same problem with his new engine..... His car switches between open/closed loop when he drives it no Error codes.......after a while his oxygen sensor hits 4mV and the BLM goes sky high.......
/N.
My friend has the same problem with his new engine..... His car switches between open/closed loop when he drives it no Error codes.......after a while his oxygen sensor hits 4mV and the BLM goes sky high.......
/N.
Last night I finally cranked the BPW up to 175 and got the BLM to say 128 at idle. The idle was smooth, no gas pouring out the tailpipe. I'm not sure what it mean.
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Car: GTA -89
Engine: Blown 415"
Transmission: 4L80E
Axle/Gears: Strange 12-bolt
It was a bad *.bin? we started from scratch again and it worked... The only changes in the bad bin was inj.const and cyl.volume and some other basics but somehow it got bad....
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/N.
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Car: 91 GTA, 91 Formula, 89 TTA
Engine: all 225+ RWHP
Transmission: all OD
Axle/Gears: Always the good ones
Sounds like:
A: It is wayyyyyy lean
B: big ole phat exhaust leak :-)
If everything else is right mechanically and using closest bin to your setup available
later
Jeremy
A: It is wayyyyyy lean
B: big ole phat exhaust leak :-)
If everything else is right mechanically and using closest bin to your setup available
later
Jeremy
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