Got a 1996 Cherokee. Tends to start smoking when ideling its a white smoke with a real strong carbon smell to it. A slight amount af water also is expelled from the pipe the jeep runs good and smooth and I have not noticed it using oil or water. I'm at a loss..... my check engine. Light. Has came on and it read upstream oxygen sensor. I replaced it. The next day same thing happened, tested and got the same code. Any ideas? Thanks.

 

Do you have overheating issues at all? White smoke could be an indication of a blown head gasket. But you would find water in the oil in that case so that doesn't sound like your issue.

What brand o2 sensor did you use? Just because a part is "new" doesn't mean that it is functional

 

nope, no over heating at all. i used a bosch o2 sensor. the plug on the o2 sensor had to be trimed onto because it did not line up with the other bracet. but was securely in place. would the oxygen sensors cause the jeep to smoke? i'm gonna go buy a compression checker today and run that test on it.

 

Does it smoke at idle but go away or seem to when driving?

 

it is only present when i am idle. if i run the jeep around town no smoke but when i stop at a red light it usually takes a minute or two but it starts back smoking. i checked the fluid level this morning again and no loss whatsoever. my oil is clean. i do not have a cat convertor on it. but it still has both oxygen sensors. i'm dumbfounded. i just got my fingers crossed that it is not the head, but it shouldn't be if im not overheating right?

 

Hi dont know. but you might have some water in muffler . just a guess.

 

Bad valve stem seals. They can be replaced without removing the head. I've done it.

 

Mine does it too. I just think of it as prevention of dry starts.

 

Check your idle temp with a heat gun just to be safe.