use some help
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From: Elk Grove Village Illinois
use some help
I have a 98 C5 with 75K miles on it and getting a code PO153 error code. I replaced the oxygen sensor and after driving the car for about an hour the code came back. Any suggestions on what I should look at next? Would appreciate any ideas or if you had a similar problem with our car and how you remedy it.
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From: Cape Coral, Florida
You most likely have a bad sensor...the wiring is OK (it’s switching) although the sensor is just “lazy”...go OEM or go home !!!!!!!...keep us advised !!
Last edited by C5 Diag; Jul 13, 2018 at 08:47 PM.
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Joined: Sep 2013
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From: Cape Coral, Florida
[QUOTE=rwobs777;1597591981]
You most likely have a bad sensor...the wiring is OK (it’s switching) although the sensor is just “lazy”...go OEM or go home !!!!!!!...keep us advised !!
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Joined: Oct 2004
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From: Elk Grove Village Illinois
Two things come to mind. Your profile indicates the car has LT headers. Did you runn the wire to the O2 snsor back far enough to insure the wire is not burned from header heat??
Second thing is what brand O2 sensor did you use for replacement? Several recent threads about the cheapo sensors out there on the market failing to work correctly on the LS engines.....
Second thing is what brand O2 sensor did you use for replacement? Several recent threads about the cheapo sensors out there on the market failing to work correctly on the LS engines.....
Any other thoughts that could be causing this issue?
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From: Cape Coral, Florida
You said you "checked" the wiring...how was this done ??....if it was a visual inspection that's NOT good enough !!...do you have a multimeter and a test light ??...if no I'm won't bother explaining how to check the wiring. A bad O2 heater circuit can "maybe" cause the sluggish O2 switching...You didn't throw a DTC for it but if it were me I'd look at it. If you had a scan tool you can see how long it takes the car to go into closed loop. My "01 goes into closed loop in about 30 seconds...if your car were to take a lot longer I would look at the heater circuit. On the PCM harness side with KOEO connect your multimeter leads to each end of the heater circuit pins...I think they are black if I can remember...should read 12 volts...I'm not sure if the heater circuit is pulse width modulated...I don't know how your electrical skills or diagnostic skills are but if this is a little to much over your head other than just changing parts take it to a reputable shop...I was actually under my car this morning getting cam/crank waveforms for my C5 library. I checked my O2 heater while I was under there and I was reading 4 ohms...3.5-14 is good....my bias voltage on the signal wire was 370 MV....350-550 mv is within spec. I see guys spend THOUANDS of dollars on mods and they don't even own a good $200.00 scan tool...I just don't understand !!...an almost 20 year old car is going to start to have issues !! ...can you ohm out your O2 heater side on your old sensor...I'm curious to know if it was good ??
p.s. My money is on a bad O2 heater circuit...and also check if you have any exhaust leaks near that sensor !!
p.s. My money is on a bad O2 heater circuit...and also check if you have any exhaust leaks near that sensor !!
Last edited by C5 Diag; Jul 14, 2018 at 08:02 PM.
