VI_Muzz

Hey guys! Ive got a 91 4 door Cherokee that I picked up in Canada a cpl years back on a snowboarding trip. (Beats renting a car) None the less fast fwd to a trip this past June from SoCal (Joshua Tree) > Moab, Utah. While driving through NV it was nearly 120 degrees outside... And the tiered stock radiator, water pump and mechanical fan were not up to the task. I enjoyed the entire week and nothing broke as long as babied it pulling off to let her "cool down". I finally saved up the money and bought a a new thermostat, water pump, aluminum radiator, 3 electric fans, and the aftermarket probe style sensor.

I ditched the mechanical fan (for the reasons above) and went with the aftermarket NAPA temp switch because I could dial it in to match the thermostat I purchased. I looked and looked and could not find any factory style switch because my jeep is a non a/c Canadian version (I was told) Here is where things get confusing to me...

Jeep run's beautiful, fans kick on when it hits gets to temp. For Christmas we decided to drive the jeep up to our Cabin in B.C. Canada from Joshua Tree and it went from getting fantastic gas mileage (pre-new cooling system) to the worst out of any vehicle I've ever owned. I mean went from nearly 400 miles per tank of gas to less than 225 miles per tank of gas. I was so paranoid I maxed out my valaro card on the way up north because I didn't want us to be stranded on Christmas with my AAA card maxed out on tows and emergency gas. Ive got no check engine lights on, and the jeep still is running great no fluctuating on the idle and no check engine lights. Threw a new k&n in, fresh oil change, new plugs & wires and still no improvements on mileage. Got over 1k in cooling system & tune up and still ****ty mileage all in the name of not over heating on this years Dirt N Drive trip to Easter Jeep Weekend. Any advice before I throw more money at what used to be my cheep jeep XJ project. Ive been told there are two coolant sensors that could be changed or the O2 sensor... But really cant afford to throw anymore money without some sound advice.

Stats: Its an Automatic, 4.0 6cyl. No A/C, NP231, 6.5 inch lift, 33inch BFG AT's, HI Pin Dana 30 in the front, Chrysler 8.25 in the rear. Has a Flex a lite radiator, 3 electric fans and the quadratec water pump

bluejeep2001

First Ive had 2 jeeps that I ran to well over 275K on the first (1992) and this one 185K (2001) both have 3 inch ome lifts ...31's and the same stock drivetrain...you running 33's on the stock 3.55 diff's...that's too low u need al least 4'10's or higher for those tires. I don't know Canada Jeeps but both mine had a 17-18 gallon tank ballpark...I got 15-17 mpg on both of them all the time ...filled up at less than 1/4 usually 15-16 gallons...that got me 225-250 per tank max NEVER was I remotely close to 400 Those 225 numbers sound normal for a big lifted jeep. With that said what does your temp run at...If your only half way to 210 you are running too cool and the ecu richens the mixture to try and get it between the last hash mark before 210 and 210. Don't know how your fans are hooked up but stock 91 temp sensor in the t-stat housing feeds the computer for richening or leaning the fuel flow. Sensor near back drivers side of head feeds the gauge only

Force

My '96 XJ is lifted 6" with 33's and 4.88 gears.
225k on the original engine.
I've never even gotten close to 400 miles out of a tank!
200-225 miles is my average range on a tank.
Maybe your gas gauge just started working!!!

s346k

what thermostat and fan settings?

bluejeep2001

Did you somehow reset your odometer from KM to miles?...its a hair more then 2 to 1