How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Jeep Service Your Own Question
Jeep Service
Jeep Service, Jeep Owner
Category: Jeep
Satisfied Customers: 4538
Experience:  14 years with AMC/Jeep Specializing with pre-1994 Jeep products.
Type Your Jeep Question Here...
Jeep Service is online now
A new question is answered every 9 seconds

1994 Jeep Cherokee Sport, 4 L inline 6. Bought it with 98K

Customer Question

1994 Jeep Cherokee Sport, 4 L inline 6. Bought it with 98K original miles recently. Took it and had the oil changed, the radiator flushed, 2 of the 3 transfer cases serviced, wipers replaced, yada, yada. The stuff you do when you buy a new used car. Drove it about 200 miles, and it overheated so that the whole thing sounded like it was falling apart in a Portland traffic jam like I've never seen before. shut it down and had it towed. Replaced the thermostat and the temperature sensor, flushed out the radiator again, had the electrical fan checked, then nursed it back home. As long as I drive it constantly, the temp guage reads just under half way. But if I get in a traffic jam, or stop and go traffic, the temp starts climbing like crazy. Don't want to hurt the car, but not sure what to do. Should also mention that original owner had the radiator replaced. I'm told that maybe flushing the system caused gunk to break loose from the heater core, and thus almost immediately dirtied the coolant. ???
JA: Have you checked the connectors on the sensor itself? It's important that they not be loose or corroded. Are you hoping to fix this yourself? What have you tried so far? What confuses you?
Customer: No haven't done that. Really want to try and do this myself, and learn, because I'm not really a mechanic.
JA: Anything else you think the mechanic should know?
Customer: Not that I can think of.
Submitted: 2 months ago.
Category: Jeep
Expert:  Jeep Service replied 2 months ago.

Hello. Welcome to Just Answer. Please allow me to assist you. This really sounds like you have a worn or otherwise faulty water pump impeller. The very first thing I would be doing, if this vehicle was in my shop, would be to pull off the water pump and inspect the impeller for damage, wear or other problems. Also, I would need to make sure that the correct water pump was in place. There are 2 water pumps that fit this engine. One for the serpentine drive system, and another for traditional V belts. One of the 2 pumps is turned backwards. Having the wrong pump installed would cause this issue, as the coolant is not being pumped thru the engine. I would also be checking the integrity of the head gasket after I made sure the water pump was OK and the correct one. A head gasket test requires a special tool and compressed air. Not something I would recommend to one who is not experienced in this test. Please let me know you have received my input; if you have any questions please feel free to ask; thanks