Check Engine Light

[bchcky]

my check engine light just came on tonight when i got back to my place. but there were no numbers associated with it. i have almost 2000 miles left before i am supposed to get my engine serviced, so i'm guessing thats not it. i recently fixed a coolant (antifreeze) leak in my engine, and had to fill it again the other night, but i checked that and that is still full, so i think my fix is holding. any other ideas what it could be for? i've heard of xj owners getting numbers that pop up and those numbers refer to a specific problem, but as far as i could tell, all that was up was the "check engine" light.

[XJNick]

Hi,

You need to check for codes on the Powertrain Control Module (PCM). You can do this with any OBD-II compliant scanner, and I believe autozone will scan vehicles for free.

Once you have a code, let us know.... Who Knows, it could be something as simple as the gas cap not being on tight

-Nick

[XJNick]

Hey, I just noticed you didn't say what year your Cherokee is...

Autozone can only scan it if it is 1996 or newer model year, as anything older used the proprietary OBD-I computer system.

-Nick

[bchcky]

well then i'm in luck nick! i have a 96. well....i guess its only luck depending on how you look at it, luck to me would be not having the CEL on in the first place. oh the joys of jeeps

[Bounty__Hunter]

If you've got a digital odometer you can try pulling the trouble code yourself. Try:

• Key off
  Push and hold the trip reset button on the odometer
  Turn key to run (not start) and back to off
  Release trip reset button
  Tell us what code appears in the odometer

Let me know if that doesn't work. If the guages cycle through their entire range you let go of the trip reset button too early.

[bchcky]

thanks for the help bounty and nick, when i tried those, all it gave me was "1.0" i thought that was kinda weird, and i called my jeep dealership, and they told me that was a weird number and probably wasnt what i was looking for.

then i realized there wasnt an auto zone near where i work, or where i live. so i asked the jeep dealership if they'd run a diagnostic for me, and they said "sure, for $35" so second thought was pep boys, cause thats right near where i work, they said "sure, its $79.99" now i understand what running a diagnostic consists of, so in no way was i ready to spend $35, let alone $80, luckily i passed an auto zone on my commute home, i stopped there and the guy helped me out in five minutes, then we proceeded to have a conversation about how pep boys and stealerships were crooks.

so the point of the story is the diagnostic told me that it was "0133" which is my oxygen sensor. and auto zone will sell me one for $50.99. i have a friend that will help me install it as i've never done it before, but does that sound steep? should i shop around? or is that a good price? (keep in mind i live in boston, and cheap is a relative term)

THANKS again for all your help guys, jeepz.com is my safehaven, and you guys make owning a jeep somewhat practical

[XJNick]

Glad you were able to get it scanned....

$50 sounds expensive to me, but for your location it might be reasonable :?

-Nick

[Bounty__Hunter]

I got mine for $40 from the Zone, Bosch.

[bchcky]

yeah, its a bosch, the manufacturer's spec. pep boys was going to screw me again and sell me the universal one for $50, which i'd then have to either get a wiring harness for or mess with a lot of wires, but the one auto zone has for $50 is the oem standard for a jeep from bosch. so i think i'm just gonna go with that. i'm supposed to go to johnny's (jps4jeep) place this weekend maybe, so hopefully i'll get it done while i'm there.

[Saurian]

Just for kicks, I tried this with my odo, got a 2.5... Jeep's running fine, for the most part. Any insight on what mine can mean? I do not have the check engine light on, btw...