No heat front or rear, gauge running cold tried everything! HELP! PLEASE! ❤️

[CaptainObvious]

I have a 1998 expedition XLT 5.4 4×4 AWD that is uncannily like yours, identical engine bay from the battery type connections which are aftermarket and a lot of other little details I was about to ask if you sold yours a couple years back cause that is when I bought mine. Anyways. I have a problem maybe you can help, the heat in the front or back doesn't work, I had a plugged heated pcv valve fitting and hoses so I had to do a bypass, my gauge always runs on the low side, tried changing sensors etc. Is there a valve for the heat or could it be a vacuum leaks somewhere crazy? Any help is greatly appreciated.

 

[Hamfisted]

Get a new thermostat as a start.

OEM Motorcraft Thermostat at Rock Auto


Yes, you should have a hot water control valve in the heater hose going to the front heater core. After you replace the thermostat feel the heater hoses and make sure they're passing hot water through them. Probably wouldn't hurt to replace the control valve if it's original.

Hot Water Control Valve at Rock Auto












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