Hi Folks. Just bought a 2000 Cherokee Sport 4.0. Runs and idles fine. But, it stalls once while warming up, almost every time. I think, just when the system should go closed loop. Today, after a half-hour ride, it stalled pulling into a parking lot. Starts back up every time. CEL works, but doesn't come on while running, idles smooth, no smoke or bad smells. I have an OBD II reader. OBDLink SX. USB device. Reads fine with key on and engine off. Start the engine, OBD goes down, up, down, up, etc.. Ignition noise, you think?
Thanks!
Harry

 

Not sure on your reader. But you might pop off the EGR and also the throttle body and check for carbon deposits and clean them out if necessary. I've had my rig's EGR (and the manifold ports below) get SO clogged up it wasn't working right. The EGR itself can get plugged, and sometimes the bellow gets cracked too and doesn't operate the way it should. Same with throttle bodies where they can get clogged up around and below the air valve.

I guess start with general troubleshooting like, all the connectors, is the temp sensor ohms correct for the temp and all that. I had a drifted temp sensor on a GM truck and when it would warm up it still ran, but ran like crap ...almost to the point of not running properly.

 

Hi! Thanks for the reply! I put the USB cable through a core, twice, and it works while running now!
I took it for a drive while running the scanner and the Jeep behaved. Snow was coming down, so I was easy with it.
Still says, "Not ready for emission testing", which seems to imply I need to drive it more. I just bought this about a week ago. By the sticker, I see it had failed inspection, 12/2018. In Jersey, there might Only be emission testing. It was in the shop before I bought it, for battery dying among other things. It has an Alpine radio that was in Demo mode, and I think the key was pulled out in ACC mode. No lights on the dash to indicate that, but upon careful examination, the buttons on the door light up.
Humm.. I see no 4WD light, either, like my 1990 Laredo had..
I'll post what happens.
Thanks!
Harry

 

Hi:
I scanned the OBD the other day and seen it said, "Ready for emission testing"! Took it down, and it passed!
I seen someplace, maybe here, it could take 40 warm-up cycles to get it 'ready'..

Thanks Folks!
Harry