zerogspacecow
NAXJA Forum User
- Location
- Acworth, GA
1998 Cherokee 4dr
4x4 Auto 4.0L w/ 160k miles
Alright, so first a little background:
On memorial day weekend I was out in the mountains camping, and it starting overheating. I believe what happened was that the thermostat stuck, pressure built up and ruptured the lower radiator hose, because there was no coolant the temperature sensor wasn't reading high. I continued to drive it to get out of woods where a tow truck could get me, and in the process ended up blowing the head gasket and warping the head.
So, yesterday I picked it up from the shop. They replaced the head gasket, machined the head, replaced the thermostat, and replaced the hose. On the way home (about and hour and half drive) it started acting up.
About a half an hour after leaving it was running normally, with the temp at about 225° (it was in the mid 90s outside), then the needle suddenly jumped up to about 250° (the first red dash) and the "check gauges" light came on. Almost immediately it dropped back down to 225°. It did that a couple more times before I pulled over to check it. Everything seemed fine, there was pressure on the upper radiator hose and it felt hot. The coolant overflow bottle was completely full and overflowing though.
After that I kept driving it home, and the temp kept jumping. Sometimes it would stay at 250° for a few minutes at a time. It also seemed to be related to the revs. If I gave it gas it would jump up, but if I let off it would drop back down. Eventually it ended up sticking at 250° for most of the rest of the way home (maybe 15 minutes).
This morning on the way to work it seemed fine. It warmed up steadily and normally, and didn't get above about 215°.
Any ideas what could be going on? It seems like maybe the temperature sensor could be bad, given how sporadically the needle jumped around (obviously it's not really possible for it to jump up or down 30° in one second). But, maybe it is overheating?
4x4 Auto 4.0L w/ 160k miles
Alright, so first a little background:
On memorial day weekend I was out in the mountains camping, and it starting overheating. I believe what happened was that the thermostat stuck, pressure built up and ruptured the lower radiator hose, because there was no coolant the temperature sensor wasn't reading high. I continued to drive it to get out of woods where a tow truck could get me, and in the process ended up blowing the head gasket and warping the head.
So, yesterday I picked it up from the shop. They replaced the head gasket, machined the head, replaced the thermostat, and replaced the hose. On the way home (about and hour and half drive) it started acting up.
About a half an hour after leaving it was running normally, with the temp at about 225° (it was in the mid 90s outside), then the needle suddenly jumped up to about 250° (the first red dash) and the "check gauges" light came on. Almost immediately it dropped back down to 225°. It did that a couple more times before I pulled over to check it. Everything seemed fine, there was pressure on the upper radiator hose and it felt hot. The coolant overflow bottle was completely full and overflowing though.
After that I kept driving it home, and the temp kept jumping. Sometimes it would stay at 250° for a few minutes at a time. It also seemed to be related to the revs. If I gave it gas it would jump up, but if I let off it would drop back down. Eventually it ended up sticking at 250° for most of the rest of the way home (maybe 15 minutes).
This morning on the way to work it seemed fine. It warmed up steadily and normally, and didn't get above about 215°.
Any ideas what could be going on? It seems like maybe the temperature sensor could be bad, given how sporadically the needle jumped around (obviously it's not really possible for it to jump up or down 30° in one second). But, maybe it is overheating?