steve1979

I have a 1998 Cherokee Classic 4.0L I6 and heat only works in defrost. Sometimes it will work correctly, not often though. When it does it is short lived. I was told this might be a vacuum leak, does anyone have a link for a diagram for the vacuum lines?

Bustedback

There is a vacuum reservoir behind the passenger side of the front bumper. Make sure it is not damaged or disconnected. There is a vacuum line that comes out of the firewall where the A/C lines go into the cab. Make sure it is not damaged or disconnected.

steve1979

Could you send a pic of this.... all i see in this area is a vacuum line hanging down near the horn. I would attach a pic but the page wont let me

tiegs89xj

Do they go down to a egged shaped canister?

steve1979

Ha ha... that explains it all... there's nothing there. I bought this thing recently and it was too clean to be for real. The last owner cleaned it up real well but after a week or so all the typical things i read in here are going wrong. All in all it was a good investment, I'm happy to not have a car payment. Brace yourselves... you will be hearing from me quite a bit in the future as i dig through the laundry list of flaws as they arise.

I looked around but all i can find for reservoirs are $60-70. Are there oem replacements that are more reasonably priced?

tiegs89xj

Go to your local junk yard. Not a commonly picked item so you should have no problem finding one there.

rideordie66

Plug the end of the line first and see if the heater works good enough for you. I cut my bumper and pulled my bottle and didn't want to find a place for it so I plugged the line after the Cruz control cluster and my heater works just fine.

steve1979

Plug it into what? There is nothing there

Bustedback

Just cap it off until you find a reservoir.

rideordie66

steve1979

I tried to cap the line but noticed no difference... found a res for 10 bucks shipped.... gonna give it a try

worleyburd

Check the lines behind the control panel, I had the same problem and I just took my radio out and pushed on the lines back there and it's been fine ever since

smusaf60

I had the same problem on my Cherokee. After looking at this thread, I looked for and found the vacuum ball in the passenger side bumper. Sure enough, the line was loose. Re installed and guess what??? It worked. You guys are great!!!

steve1979

I found one on the forum for 10 shipped and that was the problem for me too. 10 dollar fix and I have heat now!