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Wideband O2 Sensor Not Worth A F$*k!

Daboss

By Daboss,
in Engines & Forced Induction

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Daboss Experienced

Daboss

Posted
Posted

Hey everyone whats up got a wideband problem and wanted to see if anyone on here could help me out. Car is a 95 gts-t mods are pod filter with cai, fmic, 3.5" turbo back exhaust with split dump no cat, boosted up to 12 psi, stock ecu and turbo with afc neo. Ok here is the prob got a PLX wideband O2 SENSOR installed the O2 sensor in the decat pipe wired it up correctly and everything got power and the instructions stated that no calibration is needed but if you let it get warm takes 45 sec and it is exposed just to normal air the display should read air did that and air appeared on the display. Now here is the dilemna ct the car on let it get warm reset my afc neo cause Im thinking all is good and I'll be able to tune the afr's myself so I let the car get to normal operating temp took a look at my display and it reads 19 now Im cruisn at 1500 rpm to try and get the afr's right for that rpm and the display says lean and the more gas I put in the the richer it gets but i set the afc neo to +50 and the lowest afr I got was 14.5 I think!!!! What the hell is goin on. I thought skylines with stock ecu ran rich why are my afr's so lean at cruise and I did it at idle and the same thing nothing below 14.5 WHEN I have added +50% on the afc neo and when I set it back to 0 it shows lean. Can any1 help?

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BHDave Grand Master

BHDave

Posted
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Possibly try and recalibrate with the o2 sensor out of the exhaust.

On cruise your stock o2 sensor and ecu should have the mixtures fairly close to 14.5, even with a few mods. Have you got bigger injectors which may be a bit laggier than the stockers?

Daboss Experienced

Daboss

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  • Author
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Possibly try and recalibrate with the o2 sensor out of the exhaust.

On cruise your stock o2 sensor and ecu should have the mixtures fairly close to 14.5, even with a few mods. Have you got bigger injectors which may be a bit laggier than the stockers?

So you can't really tune at cruising cus what I was trying to do was tune the car to get the afr a bit lean at cruise, no I have stock injectors, still it doesn't explain why the wideband would read lean at idle and lean on the wide ban is anything over 20 there is no possible way for me to be that lean at idle with the stock ecu and no tune and like I state I had the afc neo to the max which is +50% and the afr's went to 14.5 at idle. Could the distance of the wideband O2 senor affect readings cus I have it right before the decat pipe.

QWK32 Veteran

QWK32

Posted
Posted

sensor is too hot. i get a similar probem on mine when the sensor gets to hot. and there is no point trying to tune a safc on low revs/cuising or idle because the car goes into closed loop and "tunes" itself.

Daboss Experienced

Daboss

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sensor is too hot. i get a similar probem on mine when the sensor gets to hot. and there is no point trying to tune a safc on low revs/cuising or idle because the car goes into closed loop and "tunes" itself.

Is there any fix for the sensor getting to hot? Also how can it be if the max heat for the sensor is 850 C?

paulr33 Grand Master

paulr33

Posted
Posted

there are some very specific guidelines to follow and take note of when using a wideband 02 sensor

the main ones i can think of is

mount the sensor in the right position (location and the way it faces)

the sensor must always have power when running

be closest to the turbo outlet as possible

that being said ive had a wideband sensor up my exhaust muffle and it worked fine

Daboss Experienced

Daboss

Posted
  • Author
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there are some very specific guidelines to follow and take note of when using a wideband 02 sensor

the main ones i can think of is

mount the sensor in the right position (location and the way it faces)

the sensor must always have power when running

be closest to the turbo outlet as possible(I thought it ad to be at least 24 inches away from the outlet for accurate readings at least thats what the instructions said)

that being said ive had a wideband sensor up my exhaust muffle and it worked fine

After reading that I think I figured out the problem the a$$hole that welded the bung for my O2 sensor placed the O2 sensor in the bung and it was in there for a week or so with no power to it while the car ran its daily errands. So I think the O2 senor is destroyed, damnit and I just bout it, Man guess I gatta shell a couple more bucks out for another wideband O2 sensor.

paulr33 Grand Master

paulr33

Posted
Posted
After reading that I think I figured out the problem the a$$hole that welded the bung for my O2 sensor placed the O2 sensor in the bung and it was in there for a week or so with no power to it while the car ran its daily errands. So I think the O2 senor is destroyed, damnit and I just bout it, Man guess I gatta shell a couple more bucks out for another wideband O2 sensor.

double check but i remember reading that having the sensor in the exhaust and no power certainly can kill it

then wideband sensor i had in my car was hard run off the battery terminals so you couldnt cut the power to it

this also made sure the sensor was heated up correctly

Daboss Experienced

Daboss

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double check but i remember reading that having the sensor in the exhaust and no power certainly can kill it

then wideband sensor i had in my car was hard run off the battery terminals so you couldnt cut the power to it

this also made sure the sensor was heated up correctly

So even at ignition off your sensor was still on even when you took the key out your sensor would still be on?

paulr33 Grand Master

paulr33

Posted
Posted

yes this is correct, as its a portable wideband sensor kit and not a permenant one it was setup to be temporarily setup like this on your car

so that it ran as soon as the earth terminal was connected. instead of being say on a cigarette lighter plug that could be bumped or unplugged they chose to direct hard wire it.

if you run the sensor in the exhaust stream and it looses power you risk frying the sensor, hence the hard wire method so it cant "loose" power

only took about 30 seconds to install

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