edgeman
12-14-2005, 12:19 PM
Greetings all,
I am new to this forum, and glad to reap the knowledge of all of you.
Background info:
'96 GC 3.8L, 174K miles. Regular maint. New coolant every year.
Recently had the trans rebuilt ($2500) and I had them add an auxillary trans cooler. (Don't know if that has any bearing but perhaps its connected.)
The issue:
The radiator cooling fan comes on as soon as the engine reaches normal temp, and stays on even though the weather is in the 30s (F).
When I put a heavy load on the engine such as up a steep hill at near wide open throttle for 45 seconds or more, the heat guage suddenly goes from normal to MAX. The engine temp alarm comes on. I pull over, pop the hood but the engine just doesn't seem to be hot. I get back in and let it idle for a half a minute or so and the temp guage suddenly snaps back to normal. It only does this when it is under a heavy load. If I shut the engine off while it shows overheat on the guage, and then restart right away the guage stays all the way down on cold. It may stay there for a minute then snap back to normal.
I do not see any sign of coolant in the oil or oil in the coolant. The coolant level seems to be fine.
I plan to replace the thermostat (with a fail safe one) and also the temp sensor.
If those don't solve the problem then I suppose that I need to have the coolant system checked for exhaust gasses.
I am afraid that these symptoms may be caused by a bad head gasket but I don't see much talk about these being a persistant problem on these engines.
If it is the head gasket, can the rear (left) head be removed with the engine in the van?
Any advice is much appreciated.
Rick
I am new to this forum, and glad to reap the knowledge of all of you.
Background info:
'96 GC 3.8L, 174K miles. Regular maint. New coolant every year.
Recently had the trans rebuilt ($2500) and I had them add an auxillary trans cooler. (Don't know if that has any bearing but perhaps its connected.)
The issue:
The radiator cooling fan comes on as soon as the engine reaches normal temp, and stays on even though the weather is in the 30s (F).
When I put a heavy load on the engine such as up a steep hill at near wide open throttle for 45 seconds or more, the heat guage suddenly goes from normal to MAX. The engine temp alarm comes on. I pull over, pop the hood but the engine just doesn't seem to be hot. I get back in and let it idle for a half a minute or so and the temp guage suddenly snaps back to normal. It only does this when it is under a heavy load. If I shut the engine off while it shows overheat on the guage, and then restart right away the guage stays all the way down on cold. It may stay there for a minute then snap back to normal.
I do not see any sign of coolant in the oil or oil in the coolant. The coolant level seems to be fine.
I plan to replace the thermostat (with a fail safe one) and also the temp sensor.
If those don't solve the problem then I suppose that I need to have the coolant system checked for exhaust gasses.
I am afraid that these symptoms may be caused by a bad head gasket but I don't see much talk about these being a persistant problem on these engines.
If it is the head gasket, can the rear (left) head be removed with the engine in the van?
Any advice is much appreciated.
Rick