First Check Engine Light

[kbooneKJ]

so today i got my first check engine light . its a p0133 (1,1) o2 sensor. i went to autozone to have it cleared to see if it would come back on and they said that they couldnt clear codes for ppl anymore. im debating wether to just take it to the stealership or let it go. what could happen if i just let it go, and if the ECM doesnt detect a fault, how long will that light stay on?

 

[kjweston]

10-20

 

[JeepJeepster]

Weeeeelp.. Why not just replace the O2 sensor?

 

[ThunderbirdJunkie]

Because the o2 sensor is not the root problem.
So many different things can cause an o2 sensor code that just throwing parts at it is not a solution.

This is why those stupid code-only scanners are just about useless, and if parts stores are going to pretend to diagnose a problem, they at LEAST need a REAL scanner that can provide realtime information. Not that it would stop them from saying YUP, IT'S AN O2 SENSOR every time an O2 sensor code pops up.

To summarize, Autozone or any other big box chain parts stores cannot tell you anything that you can't find out yourself on an '02-5 KJ by cycling the key on-off 3 times.

 

[LibertyTC]

In the case where I have may **** trip that has real time emissions, what then would I actually be looking to monitor? Or what the readings should be by chance while engine running ? CO2 NOX etc? Is there a set of display parameters, where is there a guide?

 

[ThunderbirdJunkie]

When the engine starts running rich, that's when o2 sensors and catalytic converters start to die.

Basically, as long as you don't drive for extended periods with a known misfire, or slack on your spark plug maintenance, you should be fine.

 

[ChiefRudy]

When was the last time you changed your engine oil? When my fiancee first bought her 02 KJ it kept giving off o2 sensor errors a day after she bought it. I even noticed light smoke coming out of the tail pipe. But, I changed the oil and and cleared the error and it never came back. It's been easy 8 months since this all happened.

So if it's been a while since your last oil change I would try that.

 

[JeepJeepster]

When was the last time you changed your engine oil? When my fiancee first bought her 02 KJ it kept giving off o2 sensor errors a day after she bought it. I even noticed light smoke coming out of the tail pipe. But, I changed the oil and and cleared the error and it never came back. It's been easy 8 months since this all happened.

So if it's been a while since your last oil change I would try that.

I do not believe changing the oil will fix an O2 problem.. Just throwing that out there though.

 

[ThunderbirdJunkie]

In THEORY, it can. Crankcase pressure can, theoretically, burble it up the filler tube, if the oil is overfilled, and then the engine COULD, again, in theory, ingest the oil IF it passes through the air filter.

Highly unlikely though

 

[ChiefRudy]

I do not believe changing the oil will fix an O2 problem.. Just throwing that out there though.

Her oil was extremely bad. it was loaded with slug and and bad enough to where the oil was burning. but like i said since i changed the oil it stopped smoking and the errors where gone.

 

[kbooneKJ]

YES! the light went off today, but i dont know why. i had my oil changed about a month and a half ago so i doubt thats the problem. I bought my kj in june of 08 with 109k and it has 122k on it now. i dont know about the spark plugs so im thinkin ill replace them this weekend and maybe do the seafoam treatment that ive read about on here...

 

[Beetlemn73]

Engine light on

To summarize, Autozone or any other big box chain parts stores cannot tell you anything that you can't find out yourself on an '02-5 KJ by cycling the key on-off 3 times.

I went to Autozone because my light came on after running out of diesel. It caused 2 codes, 1st said massive fuel leak, but 2nd code is a P0093. Fuel rail positive pressure. Are you saying I can clear the code by cycling the key on-off 3 times? Or like another poster, just remove battery for 10 minutes? Thanks

 

[HoosierJeeper]

Cycling the key on and off will only tell you what the codes are, not clear them. Removing the battery will clear them, but they might come back.

 

[ThunderbirdJunkie]

I went to Autozone because my light came on after running out of diesel. It caused 2 codes, 1st said massive fuel leak, but 2nd code is a P0093. Fuel rail positive pressure. Are you saying I can clear the code by cycling the key on-off 3 times? Or like another poster, just remove battery for 10 minutes? Thanks

You have an '06; can't check the code with the 3 key cycle thing.
You didn't get the actual number of the other code?

 

[jnaut]

In THEORY, it can. Crankcase pressure can, theoretically, burble it up the filler tube, if the oil is overfilled, and then the engine COULD, again, in theory, ingest the oil IF it passes through the air filter.

Highly unlikely though

I always wondered what happened when you overfilled your oil...