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1995 Jeep Cherokee 4.0 6cyl

jeep idle temp goes up past 210*

1. Install New Radiator 2 days ago

2. Install New Water pump. 2 yer. ago.

3. Install New Thermostat 1 week ago.

4. Install New Temperature sending unit.

5. Install New Fan Clutch.

And I am Still having the same problem. Iam at my witts end ready to junk this jeep. What else can I do. lease help

Sal

On a hot day, the engine coolant can run as high as 220-230* at idle. Just how far over 210* does the coolant get?

Tester

it will go up to about 235* then the Efan kick on and bring it right down to under 210*

Wait a minute! One of things you listed in replacing is the fan clutch. If there’s a fan clutch, there’s no electric radiator fan. Which is it?

Tester

there are to fan 1 fan clutch and the Efan for the A/C

My apologies! You are correct!

The auxillary cooling fan is controlled by the computer from the signals it recieves from the coolant temp sensor for the computer. The computer turns the fan on if the coolant temp excedes 190* and also turns on when AC is turned on. Since the fan does work, it means the relay is working. So the only other input that could cause this is a bad coolant temp sensor for the computer.

Tester

where do I fine the coolant temp sensor for the computer If you have pic. That will be great. Thank You
Sal

Well I have replace the temp guage sensor. Do not know what else I can fix or replace. can someone help me out. Thanks

210F is the standard operating temp for your JGC. My family has driven them hundreds of thousands of miles that way. My daughter’s current 4.0L I-6 '98 JGC has 175K on it, and still uses NO oil between 5000 mile oil changes. 235F is a tad high, but the fan seems to be doing it’s job of bringing it back down. Drive it and enjoy it.

I think what Tester is saying is that the engine coolant temperature sensor should be replaced; not the temperature gauge sender. These are 2 separate items and you may be confusing them.

The former sends a signal to the ECU (which controls the cooling fan) and the latter provides a variable ground for the dashboard temp gauge. The latter does not affect fan operation.

Some Fords work on the same principle of the ECT being used to provide input for fan operation.