O2 sensor replacement???
Thread Starter
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Joined: Jun 2001
Posts: 373
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From: Arms Cache, WY
O2 sensor replacement???
what are the general symptoms when one needs to be replaced, driveability, idle etc? got about 45k on present one. today, hot as hell, a/c, finally got home and, BLAH. had to let cool and start w/pedal pushed to floor. only has happened once before in similar conditions way down in the country of texas. when cranking, OX light on dash. tune up, everything's fresh including all vac hoses. have sensor and going to install anyway. right track or wrong turn? perhaps vapor lock?
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User
Joined: Jul 2001
Posts: 3,291
Likes: 2
From: Midland, Texas
Snow,
My symptoms only!
Prior to O2 replacement.
1. Rough Idle when cold.
2. Ran extremely rich.
3. Stall or near stall condition at red lights, stop signs.
4. Hunting Idle when warm - on the low side -.
5. Liked to hang around gas stations - poor mileage - .
6. Popping -light back-fire - when I let off the gas.
Let me know if you use the Universal or the high buck OEM.
If you have the sensor a splice, solder and shrink tube only takes 10-20 minutes, pulling things apart; carpet, console sidecover for the plug connector may double the time.
You have the sensor so unless you were waiting for a rainy day..... .
BTW I did not have the hard start issue.
John S. & Pattycakes
My symptoms only!
Prior to O2 replacement.
1. Rough Idle when cold.
2. Ran extremely rich.
3. Stall or near stall condition at red lights, stop signs.
4. Hunting Idle when warm - on the low side -.
5. Liked to hang around gas stations - poor mileage - .
6. Popping -light back-fire - when I let off the gas.
Let me know if you use the Universal or the high buck OEM.
If you have the sensor a splice, solder and shrink tube only takes 10-20 minutes, pulling things apart; carpet, console sidecover for the plug connector may double the time.
You have the sensor so unless you were waiting for a rainy day..... .
BTW I did not have the hard start issue.
John S. & Pattycakes
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Joined: Jun 2001
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From: Ball Ground, GA
The purpose of the oxygen sensor is to tell the ECU what the effective air/fuel ratio of the engine is at that instant. The ECU uses this output (0.0 to 1.0 vdc) to trim (sightly adjust) the amount of fuel injected in an attempt to achieve the "perfect" (stoichiometric) ratio.
The ECU only does this when the engine is running in "closed loop" mode, with good output from the oxygen sensor, normal operating temps, etc.
The engine runs in "open loop" mode, where the air/fuel ratios are based upon complex pre-programmed three-dimensional maps, until it is up to temp, with good output from the oxygen sensor, etc.
This means that the oxygen sensor basically has no effect whatsoever on starting the engine. It takes at least thirty seconds or so, even with a hot engine, for the oxygen sensor to get hot enough to give usable output to the ECU.
How well your car runs with a bad oxygen sensor (in open loop mode)depends upon how well your particular car matches the standard conditions used as a basis for programming the maps in the ECU. If your car still matches the standard conditions very well, there will be little difference. If your car has air leaks, incorrect fuel pressure,etc., etc., the car will run very poorly.
The ECU only does this when the engine is running in "closed loop" mode, with good output from the oxygen sensor, normal operating temps, etc.
The engine runs in "open loop" mode, where the air/fuel ratios are based upon complex pre-programmed three-dimensional maps, until it is up to temp, with good output from the oxygen sensor, etc.
This means that the oxygen sensor basically has no effect whatsoever on starting the engine. It takes at least thirty seconds or so, even with a hot engine, for the oxygen sensor to get hot enough to give usable output to the ECU.
How well your car runs with a bad oxygen sensor (in open loop mode)depends upon how well your particular car matches the standard conditions used as a basis for programming the maps in the ECU. If your car still matches the standard conditions very well, there will be little difference. If your car has air leaks, incorrect fuel pressure,etc., etc., the car will run very poorly.
Thread Starter
Registered User
Joined: Jun 2001
Posts: 373
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From: Arms Cache, WY
i presume if one is operating in open loop, the check engine light would be on? or does it operate in open loop after every startup?
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Thread Starter
Registered User
Joined: Jun 2001
Posts: 373
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From: Arms Cache, WY
OX sensor replaced with noticeable smoothness at speed. surging seems reduced. also, old sensor was LOOSE in the cat. and john, it was the high buck oem (for those who simply MUST know.) also, had to take fuse panel forward to release OX connector which was buried behind it.
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User
Joined: Jul 2001
Posts: 3,291
Likes: 2
From: Midland, Texas
Snow,
Someday...if I hit the LOTTO...I'll stop buying off the rack, I'll purchase OEM parts, and pay retail without so much as a whine.
My O2 connector was 'found' against the console hump under the carpet.
And Snow, I promise I won't share this bountiful, outpouring of your financials with anyone who can't read, is not on the net, deaf or dead..... you can have my word of honor on that - it's on special for $1.25. <img src="graemlins/roflmao.gif" border="0" alt="[hiha]" />
Glad to hear of some performance improvment.
Say Hi to Nancy -I'm dripping her a "SWEATER" for winter-. <img src="graemlins/beerchug.gif" border="0" alt="[cheers]" />
Someday...if I hit the LOTTO...I'll stop buying off the rack, I'll purchase OEM parts, and pay retail without so much as a whine.
My O2 connector was 'found' against the console hump under the carpet.
And Snow, I promise I won't share this bountiful, outpouring of your financials with anyone who can't read, is not on the net, deaf or dead..... you can have my word of honor on that - it's on special for $1.25. <img src="graemlins/roflmao.gif" border="0" alt="[hiha]" />
Glad to hear of some performance improvment.
Say Hi to Nancy -I'm dripping her a "SWEATER" for winter-.
<img src="graemlins/beerchug.gif" border="0" alt="[cheers]" />
Thread Starter
Registered User
Joined: Jun 2001
Posts: 373
Likes: 0
From: Arms Cache, WY
you ain't gonna' hit that lotto with digits from 0-60. try colo lotto, digits 0-50. that's your country of texas trying to increase the amount of payouts due to low playership. i've got 4 of 6 once in colo. someday the whole ball o' wax. i'm sure nancy friday sends her best too, she felt you were the most interesting of the bunch. she always gravitates towards those who have made vows though.
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