ausi02
NAXJA Forum User
- Location
- Golden, Colorado
Lets begin by saying that I haven't had any other overheating issues the the 3.5 years I have owned the vehicle. Set up: 98 AX15, 35's, 5 in of lift, roof rack, winch bumper w/o winch (so not THAT much extra weight). 135k miles on it. I drove it to Moab and back last year w/o any problems.
Now to the history. The Jeep used to run at 210 flat, didn't matter what I did. But over the past past 5 months or so I have noticed that is has started to creep up to 212 and then 215 etc. Didn't think a whole lot about it but I did notice. Then the other day after about thirty miles of highway driving (75 mph) I noticed my temp would shoot up to 245 for about 5-10 seconds and then go back down to 217-220. This spiking happened about 4 times before the top radiator hose blew. Replaced that and got the fluid flushed and replaced. Then today I was driving highway for 20 min (75mph) and had the fan on but not the AC and the temp slowly kept creeping up from 210 to 218ish and then the same spike happened like before only this time I pulled over so as not to blow a hose. The coolant in the reserve was boiling over...(I had shut it off and then put the keys in the ignition to check the temp and I think the boiling over started then) After that I drove 60 mph (then 55) for the rest of my trip to Denver and stopped once or twice. I had the heat blowing full blast and the temp still was nearing 220 (I would try to not let it get there as that was when the spike seemed to happen).
My diagnosis is that the thermostat is not functioning properly (shoulda had it repalced with the flush, oh well) but I really dont know because there is so much that can be wrong. What do you guys think? Thanks for your input!
Now to the history. The Jeep used to run at 210 flat, didn't matter what I did. But over the past past 5 months or so I have noticed that is has started to creep up to 212 and then 215 etc. Didn't think a whole lot about it but I did notice. Then the other day after about thirty miles of highway driving (75 mph) I noticed my temp would shoot up to 245 for about 5-10 seconds and then go back down to 217-220. This spiking happened about 4 times before the top radiator hose blew. Replaced that and got the fluid flushed and replaced. Then today I was driving highway for 20 min (75mph) and had the fan on but not the AC and the temp slowly kept creeping up from 210 to 218ish and then the same spike happened like before only this time I pulled over so as not to blow a hose. The coolant in the reserve was boiling over...(I had shut it off and then put the keys in the ignition to check the temp and I think the boiling over started then) After that I drove 60 mph (then 55) for the rest of my trip to Denver and stopped once or twice. I had the heat blowing full blast and the temp still was nearing 220 (I would try to not let it get there as that was when the spike seemed to happen).
My diagnosis is that the thermostat is not functioning properly (shoulda had it repalced with the flush, oh well) but I really dont know because there is so much that can be wrong. What do you guys think? Thanks for your input!