Archive for the 'Jeep' Category

2002 Jeep Liberty leaking water pump

Michelle Williams’s question:

I have a 2002 Jeep Liberty I have noticed that over the year I have had my truck the motor area seems to be getting rusty colored I took it in and they said that my water pump has a leak and said that it has been leaking for a long time how could I have over looked this I take it to get a full check up and oil change and was never told that I had a leak so what do you think I should do?”


Just replace the water pump. Many water pumps leak a little through their weep hole so that the water seal remains pliable. Mercedes Benze even states that some loss through the water pump weep hole is normal and not to replace the pump until the loss becomes large. As long as your temperature gauge ran normal, it has done no damage to the vehicle. The same truth holds for oil leaks, as most engines leak some oil as they age. Unless the leak makes a mess and starts smoking as it hits exhaust parts, it’s no big deal as long as you check to make sure the oil level stays correct inbetween oil changes.

reprogram 1996 jeep cherokee to change gears quicker

Joel Booth’s question:

how do i reprogram 1996 jeep cherokee computer to change gears quicker to up shift and save gas ???”


There is a company out there called Hypertech which has set ups to change shifting. BUT, normally these are racing type guys who want to go faster, not to shift quicker. You might contact the company and see if they make any that go the other way to make them shift quicker. BUT, realize it really wouldn’t change your gas mileage all that much. It’s the final drive gear ratio that really determines gas mileage, and you can’t change that unless you swap out rear ends with different gear ratios in them.

1996 Jeep Cherokee Set Timing After Head Gasket Replacement

Geraldo’s question:

My old 96 Jeep Cherokee is driving me crazy. I’ve got the four liter six cylinder engine and the head gasket blew. So I had a local guy put a new head gasket on, and now it won’t start. He can’t figure out what’s wrong. Do you have any suggestions?”


Let’s hope it’s a little thing. I assume the engine has been put back together correctly (and that the head gasket wasn’t put in upside down or anything crazy like that.) If that part was done correctly, a common problem is aligning the distributor correctly when putting the engine back together. Those Jeeps are REALLY particular about having the timing exactly right. So here’s an old trick: drill a small hole in the plastic distributor cap by the number one distributor cap position. Then with the engine at top dead center, the number one distributor electrode should line up with the trailing edge of the ignition rotor (and NOT the leading edge of the rotor.) I’ve seen this stump a lot of guys in the past, it’s a pretty simple fix. Then you just go and buy a new distributor cap, they don’t cost much on that Jeep.

Jeep 2002, 4.0 L, 120K has a Trouble code PO456 and Pending code PO442

Peter’s question:

Hi,  Jeep 2002, 4.0 L, 120K has a Trouble code PO456 and Pending code PO442 – Evaporative Emission System. The MIL is ON. What do you recommend me to do? Thank you, Peter ”


Those are both codes for small evap system leaks–The hardest ones to find. They can be REALLY small. The only way to even attempt to find them is to hook up a smoke machine to the evap system and search for leaks.Check for hose connection leaks, the evap pressure sensor for leaks, the evap cannister purge valve (a very common problem in jeeps), and the evap cannister itself for leaks. The larger leaks are pretty easy to catch, but those small ones can be absolute monsters. Good Luck,