maxpoer

Started and pulled my 1996 Cherokee into the garage today to replace blower motor and blower resistor. It started fine and ran fine pulling into the garage. replace blower motor and resistor and went to pull the truck back out of the garage and it wouldn't start. I hit the gas pedal a few times while cranking and it fired up, but as soon as I take my foot off the gas it stumbles and dies. I can start it back up by giving it some gas while cranking, and if I hold it at about 1k rpm with the accelerator, it runs fine, and revs fine, but as soon as I let off it dies.

Now the blower motor was pretty minor surgery, just had to remove the windshield washer tank, swap the motor, and put it back in. Is there anything over there that I could have bumped that would have caused this behavior right out of the blue? The hood was up with the light on so I threw the battery charger on it for an hour or two, but still no better, plus I figure if it has enough juice to start the truck, it should be able to idle. Any thoughts woudl be greatly appreciated, this is a real mystery, and unfortunately one I don't have a lot of time to solve. Thanks!

Willys55

Evap purge solenoid is right in the area where you were working, check to see if the plastic vacuum line is cracked from where it meets the solenoid to the throttle body

HDTony

Did you have the battery disconnected? Sounds exactly like what was happening to me when I had a weak battery. the computer would loose it's memory and wouldn't start idling till I drove it for a while

maxpoer

I didn't have the battery disconnected, and the light under the hood was on most of the day. I'm sure the battery was pretty low. I'll throw the charger on it and let it go overnight to make sure it's back to 100% tomorrow.

How long did you have to drive it around before it "relearned" how to idle? This was right out of the blue so I would like to eliminate anything like this before I start tinkering with stuff that could be perfectly fine.

maxpoer

Well, here's the solution. Charged up the battery overnight, disconnected the cables and held them together (as recommended by others on forum to reset the computer) and hooked everything back up. I hit the key to start it and it started faster than it ever has since I've owned it and settled into a nice smooth idle. So now does it not only idle like it used to, it actually starts BETTER than it used to.

Big thanks to everyone here. This was a weird situation that I'm not even sure how I would have began to troubleshoot, but I'm sure it wouldn't have been with the battery and resetting the computer since at no time was the battery even low enough to not start the truck. Searching here gave me some stuff to try before ripping things apart and that ended up saving me big time and probably $$.