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need a lil help.. 98 f-150 heater problem

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For some odd reason my heater dosnt work. it only blows look warm air and it sucks. It used to work killer but now its starting to piss me off..

Truck is a 98 f-150.

anything i should look at?

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For some odd reason my heater dosnt work. it only blows look warm air and it sucks. It used to work killer but now its starting to piss me off..

Truck is a 98 f-150.

anything i should look at?

Yes, its either low on coolant, over cooling (bad thermostat) or a plugged heater core (is the coolant rusty looking?)

But the heater cores on these rigs takes about 20 minutes to replace if that is the problem.

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i figured it was low on coolant.. im just running water and it does empty rather quick.. i havnt changed the thermo since ive owned it so it could be the problem.

and the coolant looks clean with nothing in it..

thanks for ur help..

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i figured it was low on coolant.. im just running water and it does empty rather quick.. i havnt changed the thermo since ive owned it so it could be the problem.

and the coolant looks clean with nothing in it..

thanks for ur help..

You need to address the water loss issue and get actual antifreeze in there before you do more damage. Coolant not only improves heat transfer, but lubricates the water pump and prevents corrosion.

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Yes, its either low on coolant, over cooling (bad thermostat) or a plugged heater core (is the coolant rusty looking?)

But the heater cores on these rigs takes about 20 minutes to replace if that is the problem.

not sure when they revised the IP in the F150. However, in my 2001, it took 7 hours to swap the heater core following the real OEM service manual with some extra tips off of a F150 website. I could probably do it in 3-4 hours if I had to do it again since I waste a bit of time putting stuff back together that didn't need to come apart. I tried to find a different way of doing it than pulling the whole thing apart. Anyway, I design interior car parts so I am pretty comfortable with knowing how to take them apart and it still took a while.

That said, it's probably the coolant level as previously stated. When the heater core goes bad in a F150 it usually results in puking antifreeze into the airducts. The only other thing it could be is an issue with one of the vacume lines that move the air door inside the duct work.

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as ChrisKring stated the 97 and up F150 requires removing the complete dash assembly. we do have alot of trouble with plugged or leaking cores. The temp doors are bad about breaking too. But you do need to fix the leak first.

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theirs nothing leaking out of the motor.. and theirs a 70-30 ratio of water to coolant within the motor.. truck dosnt overheat and as soon as it gets to operating temp it dosnt budge.... i havnt addressed the heating problem as i actually forgot about it as the weather has been nice.. but im thinking the thermostat is stuck open.. its 11 years old and never been changed..

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Ran into an issue with a heater not making heat one time. After the obvious things like thermstat, low coolant, etc, I pulled the hoses off that run to and from the heater. I stuck a garden hose in the heater intake hose. Water barely ran thru the heater. I stuck it in the outlet side and flushed water back thru the heater and a bunch of crud came out. It had been stuck in there under pressure I suppose, but once it was out of there the heater worked good again. Just an idea. It was not on an F 150, so I'm not familiar with your set up. Good luck....

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as ChrisKring stated the 97 and up F150 requires removing the complete dash assembly. we do have alot of trouble with plugged or leaking cores. The temp doors are bad about breaking too. But you do need to fix the leak first.

Wow, I remember unhooking a pair of heater hoses from the heater core, taking the glove box door off, removing a small inspection panel and sliding the heater core out. I assume they just kept that same layout. Must have been the prior generation.

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Never run straight water in a cooling system with an Aluminum Radiator or heater core. You need a 50/50 mix or slightly more coolant to properly protect the Aluminum components.

This ain't 1967 and the car ain't a 62 Buick with Heavy duty copper parts kids.:)

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You need to verify the temp blend door motor/door is working....and not stuck at mid travel...They do go bad

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You need to verify the temp blend door motor/door is working....and not stuck at mid travel...They do go bad

thats the next thing im going to look at after i change out the thermo.

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