problems with 02 sensors (keep having to replace them )

[maldo]

95 Trans am with procharged 383 lt1 long tubes all the works.. and my o2 sesnros don't last more then a few thousand miles before they take a dump ... this car has been tuned so i know for a fact that the engine is running fine.. i have changed plugs injectors etc just to make sure (plus i have a scan mast that monitors everything so nothing is out of wake .... has this happen to anyone else???? i am tired of spending so much on 02 sensors

[GetMore]

I'm gonna ask a few questions. Some of them might be stupid, but bear with me.
Are these heated sensors? How many wires are on these sensors? Are you running one sensor or two? Do they die at the same time? Where is the sensor bung mounted? Have you checked for power to the sensors? What do they do when they fail? What kind of fuel are you running?

[MonzaRacer]

If you dont have them in proper exhaust area, too hot or too cold they will eventually fail.
They need at least 600 degrees to work if they are melting then they are getting too hot, if they are too cool you may need heated ot sensors if they are not.
Also which brand are you running? I have serious issues with anything but AC Delco in GM applications.

[maldo]

I'm gonna ask a few questions. Some of them might be stupid, but bear with me.
Are these heated sensors? How many wires are on these sensors? Are you running one sensor or two? Do they die at the same time? Where is the sensor bung mounted? Have you checked for power to the sensors? What do they do when they fail? What kind of fuel are you running?


1) i believe they are heated 02's it has 4 wires..

2) ON MY LT1 i am running jet hot long tube 1 3/4 Headers which are the same as the hooker ..

3) 02 bungs are at the end of the collector...

4) power checks out fine

5) This time the right one died first but they go out about the same time..

6) car is well tuned and if there were any abnormal stuff going on i would see it right away in the scan master and plugs ...

7) when they fail one or both will get lazy (I can see it on the scan master and see the fuel trim and block learns start to change to compensate plus the car starts to run like crap because one side will show lean etc )


some have said it the jet hot coating that's killing the sensor that i i posted to see if other are having the same problem

[gEtyOpAPiOn]

What computer are you using. And what color are the o2 tips when you take them out?

[avewhtboy]

Another thing to keep in mind, most manufacturers recommend using anti-seize, some even have it on the threads already, if that gets on the sensor it will kill it too.

From what you have described I would guess the location may be too far down the tubes?

Do you see anything on the old sensors? maybe post a few pictures of the bad sensors if you have them.

[maldo]

what computer are you using. And what color are the o2 tips when you take them out?

stock gm obd1 tuned for the 383 procharged set up

plugs look great when i pull the o2 sensors out they look pretty good not bad at all ...

[gkring]

Does the car ever see any leaded fuel, as in race gas at the track? Obviously that will kill the sensors fairly quickly and give the problems you describe. Any chance of hooking up a wideband to verify what the factory sensors are seeing to rule out bad grounds or signals? Does sound weird.

[maldo]

Does the car ever see any leaded fuel, as in race gas at the track? Obviously that will kill the sensors fairly quickly and give the problems you describe. Any chance of hooking up a wideband to verify what the factory sensors are seeing to rule out bad grounds or signals? Does sound weird.

no leaded gas was tuned on the dyno all ok


http://www.youtube.com/watch?v=X6rbjmW2Xn8

[mrn2obelvedere]

If its a reflashed stock gm computer I would take it to a dealership and ask what they think. Maybe its a problem some of their mechanics have seen before? Just a shot in the dark.

[maldo]

If its a reflashed stock gm computer I would take it to a dealership and ask what they think. Maybe its a problem some of their mechanics have seen before? Just a shot in the dark.


naaa nothing they can help me with

[gEtyOpAPiOn]

Well I know of one car that had water coolant leak on the intake and that would mess up the o2 sensors it was just a small leak almost unoticed

[DeltaT]

In reference to your comment farther back, I have Jet-Hot on my headers and no O2 problems.

Jim

[maldo]

Well I know of one car that had water coolant leak on the intake and that would mess up the o2 sensors it was just a small leak almost unoticed

this is an lt1 engine so no coolant goes through the intake

[maldo]

In reference to your comment farther back, I have Jet-Hot on my headers and no O2 problems.

Jim


ok thats good to know becasue I did not think that could be the problem

[mrn2obelvedere]

When do heated O2 sensors know when to stop heating?

[maldo]

When do heated O2 sensors know when to stop heating?


?? hmm i dont know

[gEtyOpAPiOn]

i think it stays on because one end is grounded and the other one gets power from ignition then there is hi and lo res. so i would guess it just stays on

[mrn2obelvedere]

i think it stays on because one end is grounded and the other one gets power from ignition then there is hi and lo res. so i would guess it just stays on

I remember when we were having problems eating O2 sensors on our FSAE car in college. It had a motec ecu. I seem to recall that for some reason the O2 element was not turning off or something like that. We kept burning up wideband sensors to the tune of $200 a pop. I'm sorry but I can't remember the exact cause of the problem nor can I remember if the sensor was "getting stuck on".

What about the proximity of the sensor to the engine? Could the gasses be cooling down too much?