FallenDown

I have a 1996 Cherokee Sport with a 4.0. My old radiator was leaking bad and my jeep was getting hot with coolant coming out of the overflow. So I changed it out along with the water pump, thermostat, thermostat housing, and radiator hoses while I was in there. When I went to start it up, there was a loud screeching noise coming from the water pump. It went away after a while, but every time I start it up it comes back. And now my check engine light is on. I haven't driven it anywhere, and it's just sitting in the shop right now. It's a Mopar water pump, v9900083. I confirmed the part number with the dealership, so I'm not really sure what the issue is. I'm pretty new to working on jeeps, so any help would be appreciated.

robertj

It's possible the water pump is bad out of the box, but I don't see how that would trip a CEL unless you let it overheat. Get the code read and let us know what it says.

FallenDown

Nah, I didn't let it overheat. It came on right when I started it up. Wasn't on before I took the old radiator, pump, thermostat, and housing out. Not really sure how I can get the code without driving it somewhere as is...

RubenZ

are you sure CEL is related to Water Pump? I accidentally forgot to plug my Temp sensor at the T-Stat housing and it immediately through a code. As for your water Pump, did you tighten the belt correctly? When I replaced my Cylinder Head last weak and had to remove power steering pump I had to loosen the Drive Belt. Well now that I put it all back together its been squealing at start up as well. I need to see if Its either too tight or loose. maybe thats it.

FallenDown

I'm not sure the CEL is water pump related. It could be related to something being unplugged, like you ran into. Not sure about the tension, as I've never done it before. Had someone helping me out with it. Plan on going back to the shop tomorrow to check it out. I just know that the squealing noise was coming directly from the water pump and it was pretty ear piercingly horrible.

FallenDown

So, apparently my XJ was low on transmission fluid because my dad backed it out of the shop bay quickly when it had the radiator out so he could use the lift for another vehicle. So I topped it off and the CEL went away and hasn't been back since. I tightened up the belt today and the noise from the water pump went away immediately. It's running strong and cool now. No overheating. So, overall a good outcome. A lot less work than I expected! Thanks for the suggestions! RubenZ was spot on about the belt.