I have a 99 4.0 that overheated on me during a long roadtrip. By the time I got to a service station, I had to dump 2 qts of oil in and fill the radiator. Now that I am home and all fluids are full, its still overheating and I dont know why. Here are the 'stats/clues':
1. All fluids are full.
2. There is NO smoke coming from exhaust pipe.
3. There are NO weird noises coming from engine.
4. There is no water in the oil.
5. Fans and serpentine belt are intact and operating.
6. For the first 10 minutes after starting car, it sounds, smells and runs normally. After 10 minutes, it smells hot, runs rough and wants to stall while in gear at a standstill. Obviously in "overheat mode".
7. Temp guage is at 0 when car is started, goes up to and stays at about 215 after 10 minutes- even when it smells alot hotter than 215. When overheating first occurred, temp guage was actually pegged in the 'red zone'.
8. Oil pressure gauge indicates 80. Not sure if thats accurate either though. It does go to 0 when car is turned off, but when key is "on" and car is NOT running, gauge reads 80.. hmmm...
9. When car overheated, I tried turning my heater on to circulate more water, but heater now blows cold only (worked fine prior to this). Even now that radiator is full, heat will not blow hot- no matter what setting I use.
Im guessing either water pump or oil pump failure.. leaning towards water pump since heater wont work??? Is there a way to test both pumps to see if they are working properly? Or is there something else that could be wrong?
Please help, this is my only car!!!!!