Check Engine light still on

[blkroze1982]

Got an error code telling me to change the oxygen sensor. Replaced it and the Check Engine light still comes on after a couple minutes.

 

[12step]

No you got an error code telling you that the oxygen sensor was indicating a lean or rich condition so were you running rich or lean

 

[blkroze1982]

Well, the oxygen sensor was bad. I was just looking for an easy way to clear the code. No need to be a smartass.

 

[Bryan22]

He's not being a smartass. if a new sensor didn't get the light to go off, it wasn't the problem. I'd try cleaning the MAF.

 

[Earl43P]

Check the HEGO fuse, should be #18 in the fuse panel (cab).

It would be helpful to know the code #.


To "reset" the PCM, disconnect the battery -, turn on/off headlamps, reconnect.

 

[12step]

I'd rather be a smart ass than a dumb ass but that dosent change the fact that u still haven't given us a code number u can turn the light out by disconnecting the negative battery cable for a few minutes if the light comes on within a few minutes you have a hard fault go get that checked give us a code number and we can help u from there

 

[Rogue_Wulff]

Sometimes, replacing a faulty part doesn't make the light go off. I accidentally broke the coolant temp sensor on my 95, which predictably caused a check engine light.
Replacing the CT sensor, which was completely broken in two, did not make the light go off. Erased the code, and the light went out.
Fast forward a couple months, and I reset the timing belt as it had been installed incorrectly (ironically, this was what I was trying to check when I broke the CTS). Since I had previously broke the CTS, I unplugged it before removing the timing belt cover. Forgot to plug it back in before starting the truck, which again set a CEL. Once again, the light did not go back off until I plugged in a code scanner and erased the code.

 

[Bryan22]

On an obd1 vehicle i've never had the light stay on after fixing the problem.

 

[Rogue_Wulff]

Dunno. Only OBD1 vehicle I've ever owned is my Nissan. It doesn't even have a light on the dash. It's hidden on top of the ECU, under the passenger seat. With 240K+ on it, I've never had to use the built-in diagnostic mode on that truck.