oxygen sensor
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oxygen sensor
I believe my Oxygen sensors are not good, gas milage poor and the milage is at 65k, time for a change. On my 95 I think there are 3 sensors and the choice on the forum seems to be Ac delco for compatibility reasons. Is this a hard removal and install and any pointers would greatly appriciated. Thank you. mike t
Melting Slicks
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From: Sebastian Florida
St. Jude Donor '06
Why do you say the O2 sensors?
Are you throwing any codes?
ACDelco are good, so are Bosch. But as in most tuneup parts, this just my opinion. O2's will usually throw a code, if not I would look to wires and plugs, then PCV, Coil and opti.
Are you throwing any codes?
ACDelco are good, so are Bosch. But as in most tuneup parts, this just my opinion. O2's will usually throw a code, if not I would look to wires and plugs, then PCV, Coil and opti.
Last edited by Randy93; Apr 14, 2006 at 02:37 PM.
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I like AC/Delco and Denso. You can purchase both of them here at a reasonable price and get free shipping.
http://www.buyautoparts.com/gm-parts/
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Thank you for the reply, no I have not seen any codes, but did hook up a ez scan 5000 it said system was in closed loop, left O2 sensor at 1003 mVolts and rt sensor at 928 mVolts. I thought open loop to mean the O2 sensor was interacting with the EMC and setting fuel mixture settings, otherwise the system would run rich, use lots of fuel and ruin the cat. Maybe I got this all wrong.
Le Mans Master
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From: San Diego, Ca
My feeling is that these things rarely if ever go bad (except when they're mishandled). Federal and partcularly CA (and everything built since the early '80's has the same equipment) emissions warrantys are so damning, that if they were failing on a regular basis, the OEM'S would be inundated with recall orders. Ain't never happened - not even once. In any event, better to capture a data stream - not just a single event - or to look at your long term fuel trim - Block Learn or BLM which is numerical representation of how the ECM is delivering fuel based on what the O2's are telling it. Try it at various RPMS - say idle and then 2200 or a steady 50 to 60 mph cruise. Post what you get - both sides.
Burning Brakes
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From: Camden SC
Originally Posted by SunCr
My feeling is that these things rarely if ever go bad (except when they're mishandled). Federal and partcularly CA (and everything built since the early '80's has the same equipment) emissions warrantys are so damning, that if they were failing on a regular basis, the OEM'S would be inundated with recall orders. Ain't never happened - not even once. In any event, better to capture a data stream - not just a single event - or to look at your long term fuel trim - Block Learn or BLM which is numerical representation of how the ECM is delivering fuel based on what the O2's are telling it. Try it at various RPMS - say idle and then 2200 or a steady 50 to 60 mph cruise. Post what you get - both sides.
SunCr is on track. The block learn values need to be checked. A "weak" sensor(s) on OBD1 cars are somewhat more difficult to detect. If voltage values represent a lean condition, the system will command rich and your mileage will suffer.
On OBD2 cars, the system performs a response time test, namely, rich to lean and lean to rich transistion times and evaluates the sensors sensitivity. Another reason I like OBD2 systems.
If the OBD1 system has not set a sensor code, or moved the block learn mode(BLM) far enough to set a BLM code, you're in a more subjective mode. You can hook up a scanner and watch the sensor voltage values as you accelerate, idle, etc. You can also remove the sensor and visually inspect. Again, subjective.
Having said all that, when I did some exhaust work on my car at 50K, I just replaced the sensor cause I felt like it and had only one sensor.
As stated earlier, check the BLM(long term fuel trim)and let us know.
dlmeyers 90 coupe zf6 3pseed shocks
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Originally Posted by mike t
Thank you for the reply, no I have not seen any codes, but did hook up a ez scan 5000 it said system was in closed loop, left O2 sensor at 1003 mVolts and rt sensor at 928 mVolts. I thought open loop to mean the O2 sensor was interacting with the EMC and setting fuel mixture settings, otherwise the system would run rich, use lots of fuel and ruin the cat. Maybe I got this all wrong.
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I have had an O2 sensor go out on my '94 LT1 and it didn't throw a code. Not even the driveablility guy at the dealership caught it, but when looking at the voltage of the O2's one would randomly drop in voltage to 39 and after replacing it, all my driveability problems went away.
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Thank you all for great information, the Acdelco sensor is not expensive, on the net new at $40 and I am sure cheaper. I just got into corvettes 2 years ago and when I am not in the car thining about it. Had a major tune up 16k ago and the car runs fine, in fact I plan to run from boston MA to Hilton Head SC for a one day meeting, did it last year and it was fantastic. Any excuse. I am 65 now and from England and every time I climb over that sill and drop down into the cockpit I feel like I am in WW2 fighter, Spitfire or P-Mustang once tha big V8 fires up. Love it. One fantastic American Sports car
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From: Good health is merely the slowest possible rate at which one can die
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Originally Posted by Randy93
O2's will usually throw a code
