I have a 97 Escort, that I have been having heating problems with. Thermostat has been changed twice, and the last time, bypass gasket was also changed. I have to drive it for approx. 5 miles before it gets into operating range. Once there, it heats fine until I get into town, then goes down again. No one seems to have an answer. Any help would be appreciated. Thanks Shorty
Slow Warm-up on 1997 Ford Escort
what does your temp gauge say when the car is heating normally? It sounds like there is a circulation problem that is helped by the faster speed of the engine when you are on the highway. It could be that the impeller of your water pump is worn and it takes a higher engine rpm to circulate the water, especially in a cold environment like winter in ND. Another possibility is that your heater core could be restricted and the higher engine rpm pushes/forces more coolant flow. It is pretty simple to flush out a heater core while checking a water pump impeller is more involved and requires timing belt component removal. I would begin with flow testing the heater core by disconnecting the heater hoses and either blowing through it or using a hose to flow water through it. If it is restricted, then you can flush it with some radiator flush. It is not an uncommon problem, especially if the coolant changes have been infrequent ( like more than every 30,000 miles ).
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Change your thermostat housing/water outlet. It has a plastic part in it that melts when the car overheats and causes the coolent to bypass the thermostat. It is a failsafe to protect the head incase the thermostat will not open. Motorcraft makes the part with ect sensor, temp sensor, thermostat and gasket. I installed one on my daughtor's car and it solved the problem. Look on youtube for the video.
check your radiator fan motor if it's working, maybe it failed or wearing out and needs to replace.by turning on the ac if it's working continously....