low temp / no heat

[swetherton]

have a problem with heat. temp guage below normal 150 degrees or less.
new thermostat, new heater core, and hoses. new coolant.
can block off rad and still will not heat up. need help before i freeze and can't type no more. thankkkksssss. can contact at [email protected]

[476259]

We are having the same problem here. We are at a loss. The thermostat has been replaced twice, ect sensor (pcm)has been replaced, still stays in open loop, ect is around 180°f. It never gets hotter than that. Actual coolant temp is around 160°f at the thermostat housing.

[badfunkn]

Me too, replaced the heater core, thermostat and backflushed the system and still no heat. Water pump next?

[476259]

check your fuel pressure if it is over 35psi replace the fuel pressure regulator. mine was 60+psi!

[EVH5150]

just wondering, what temp is you T-stat set at? Maybe you need to go with a hotter T-stat range. 190 degree range. If thats not it, it may be the water pump crapping out on you (hopefully not though)

[badfunkn]

Fuel Pressure!!??? Does that have anything to do with it?

My T-stat is 190 degree.

[EVH5150]

Another possibility is that it might be a faulty blower motor that would keep hot air from being forced into the heater core. That's located on the right side of the engine compartment against the firewall. Just another thought.

[badfunkn]

Blower motor is fine. There isn't any water getting to the heater core. No blockages that I can find, water flows fine when I hook up the backflush kit. There isn't a control valve on ths year Ranger either. I'm stumped.

[EVH5150]

It says in the manual, to check to see if the water pump is defective, run the truck at normal operating temp and to squeeze the upper radiator hose. you should feel a pressure surge as the hose is released. other than that, yeah I'm stumped too. Sorry

[badfunkn]

Yeah you're not the only one either, I've got this problem floating around a couple of other forums too. I haven't gotten a good answer yet. The only thing left to do is replace the pump, maybe the vanes are deteriorating and just haven't got bad enough to affect the engine temp. I've tried sqezzing the hose and I can feel the water flowing through it, I don't know if I would call it a "surge" though.

[rodneys]

Have you checked the Heater Control Valve,,,or maybe the vac line has come off not operating the valve,,just a thought.Sorry I didn't see the post above.

[476259]

An over rich condition will cause the engine to run cooler, ie. not getting heat out of your heater. If the thermostat is good it will regulate the temperture no matter what. The coolant will be forced to stay in the block until it reaches 192f (oem) then it will open allowing cold coolant to enter from the radiator. The heater inlet runs off the engine side so I would check the themostat and then check fuel pressure. Is your check engine light on?

[badfunkn]

No the check engine light is not on. The T-Stat seems to be working OK, I can tell when opens and closes. I haven't checked the coolant temp to see if it's 192F though. Would high fuel pressure cause the coolant not to flow through the heater core? I could understand the coolant not getting hot enough to create heat but not interrupting the flow altogether.

[476259]

Try removing the outlet hose on the heater core to see if it has coolant flowing through it when running, if not you need to check for blockage in the hose or engine block or possible a bad pump.

[badfunkn]

Definitely no blockage, I put a hose on both inlet and outlet hoses and ran water through easily both ways. Pulled off both hoses (one at a time) with engine running and no coolant flowing through. I believe the only thing it can be is the water pump. Doesn't make sense because my engine temp is steady in the normal range.