Running super COLD all the time

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FX4FOUR

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Got a 98. 220 on the clock, runs great but COLD. I man absolutely 99% cold. Idle 20 min heater hose line Slightly warm.

I know, check the thermostat, waterpump all the basics, did. Seem to be in working condition.

I did notice that the fan makes that roar of rushing air like it is engaged, but the fan bearing is not stiff, loose, frozen in place.
I can’t imagine a engaged clutch fan would cause a slightly warm heater hose.

On to the inside, door opens and closes ok, transfer of vents is ok. Just cold. Not really a big deal now that warm weather is here, but I really have not driven it on any long drives. Just the idle test as mentioned here. I would hate to get out and have it OVERHEAT and melt on me.

So any suggestions or know causes or fixes would be of help. P.S. getting ready to put a new intake on it. The thermostat bolts were super tight going out and in.

Thanks !
JP
 

Dennis_H

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Any chance you put in one of those 'never fail closed' thermostats? I made that mistake on a dodge full size van where it had to be changed by feel alone. It stuck open almost immediately and I got to do the job again before the next winter. If you are replacing the intake anyway, replace it with a Motorcraft.
 

Dimz

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My 00 5.4 runs cold at low speeds. I pulled the restrictor in the line that goes from intake to heater core that helped a bit, changed the heater core and thermostat, a little warmer but still its just the design. So many lines and airflow. It's more of a highway cruiser so its designed to not overheat at high rpm. Heater cores do get plugged up alot on these!
 
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