o2 sensor after o2 sensor....

[mudbog42]

Does anyone know why my truck keeps going through so many o2 sensors I have already replaced them 3 or 4 times within the last 6 months and they keep going bad again and again . I don't know what is causing this.
Any help would be greatly appreciated

86 K-5 with a 350

 

[dyeager535]

How do you know they are bad?

O2 sensors are extremely sensitive to silicone (as in RTV) enough that using it in the garage with the vehicle can kill them.

 

[ssped]

is there any oil getting into the back of the connector or the top of the sensor. that will kill it also. is the engine running rich for another reason like a bad maf sensor or something. to hot of a plug?

just a few things to look at.

 

[mudbog42]

How do you know they are bad?

O2 sensors are extremely sensitive to silicone (as in RTV) enough that using it in the garage with the vehicle can kill them.

The check engine will come on and when I scan it, it always says o2 sensor failure. Also there is no oil or anything around the sensor or connector
I'm stumped...

 

[ssped]

I dont remember if you can check it with a volt meter and see the oscilation but I know we can view them live on the scanner at work. something is probably burning them out. is the truck smoking or burning oil? what year and type fuel system is on it? Also check the actual harness. O2 sensors operate on very low voltage .01 to .09 volts(if I remember that correctly too) so any resistance looks like a bad sensor.

 

[sweetk30]

biggest mistake ever. just cause the code shows o2 problem dosnt mean o2 sensor bad. thats just throwing parts at it. you need the flow chart of tests to find out what is making it throw the code.

and what specs on the ride? year/make/model/motor/????

i dont recall any codes that say o2 is failed. thay say out of range/ slow responce / low or high signal / o2 heater low or high voltage / stuff like that. gve us the specs and the exact code # or #'s .

 

[sweetk30]

you need a scope to see pattern off a running o2 sensor. and what brand are you running?

 

[sled_dog]

we need to know more and the specific codes. I bet you are getting some rich or lean codes and the problem is NOT the O2 sensors.

Had the brainiacs at Autozone scan my 97 before I knew any better. They told me the codes were "you need all new O2 sensors"(4 of them mind you). So being 19 and having **** for money at the time I saved and put 4 in.... yea did nothing. What were the codes? Bank 1 & 2 Rich... O2 sensors were reading fine, they were telling me it was rich.

 

[mudbog42]

Its an 86 K-5 Blazer with a 350 and california emissions equipped.
The scanner I have says oxygen sensor failure, I forget the code number because I just reset the computer and so far has not came back but sure it will soon enough
Also I've been using the bosch o2 sensors from the local auto parts stores

 

[mudbog42]

The truck is not smoking or buring any oil, its got a new jasper motor in it and haven't had any problems with losing oil since its been installed

 

[mudbog42]

I dont remember if you can check it with a volt meter and see the oscilation but I know we can view them live on the scanner at work. something is probably burning them out. is the truck smoking or burning oil? what year and type fuel system is on it? Also check the actual harness. O2 sensors operate on very low voltage .01 to .09 volts(if I remember that correctly too) so any resistance looks like a bad sensor.

Its still got the electronic Q-jet on it which has been built by recarbco within the last year and I've got it tuned within 450 mv read by the o2 sensor

 

[ssped]

does the engine have a cam in it? How bout exhaust leaks before the o2 sensor or around the Bung that the o2 scres into? Did you use anti sieze on the threads when installing it? It is going to be something simple on that set up.

 

[mudbog42]

does the engine have a cam in it? How bout exhaust leaks before the o2 sensor or around the Bung that the o2 scres into? Did you use anti sieze on the threads when installing it? It is going to be something simple on that set up.

The engine just has the same cam that came with the jasper motor, no exhaust leaks, and no I haven't used any anti sieze on the o2 sensors... could that be it????

 

[ssped]

Try another sensor and see how long she lasts. could just be another crappy Bosch o2 sensor.

 

[sweetk30]

Try another sensor and see how long she lasts. could just be another crappy Bosch o2 sensor.

no problems with bosch sensors here. thay are in all my rides. and there is basicly only 2 good brands out there. and thay are one of them. and o.e. equiped.

 

[dyeager535]

Bosch has a poor reputation. (head over to thirdgen.org for the problems)

Got one in my truck (before I had heard of the problems) but so far so good with it.

Delco when this one goes though.

 

[mudbog42]

Yeah I think I need to just break down and get a delco next time the code comes back and just give up on bosch

 

[6.2Blazer]

As already mentioned I would say there is a good chance there is nothing wrong with the actual O2 sensor. I've spent a lot of time working on newer vehicles and I don't remember them actually having a code saying the sensor itself was bad, it was always the reading was some how out of scope...sometimes it was an actual bad reading caused by either the sensor or wiring harness, and sometimes it was because the engine was doing something weird and the sensor was actually doing it's job and trying to tell you something else was wrong.

Speaking of the wiring harness, make sure you thoroughly check it out. Of the times when we narrowed down the issue to an actual incorrect reading, about half of time it was something in the harness or connectors and not the actual sensor.

 

[ssped]

Speaking of the wiring harness, make sure you thoroughly check it out. Of the times when we narrowed down the issue to an actual incorrect reading, about half of time it was something in the harness or connectors and not the actual sensor.

DITTO