looking for some mechanic help

[ljwhite174]

Hi everyone,

i am looking for some help with my Ram, it has a 5.2L and i am having a problem with it heating up in this cold snap. its a 98' and it wont seem to heat up past 150 degrees, i changed the thermostat and flushed the cooling system and put in new 50/50 mix, and it didnt change, it is also stuck in defrost which i am asuming is from a bad vaccum pump on the vendor well under the hood, its a old farm truck that i just use for work and am kind of at a little bit of a loss at why it wont get any hotter or blow hot air in the cab the new thermostat was a 195 degree replacement, i dont want to sound stupid but are all the heater and a/c controls run by the vaccum pump.

 

[NYCruiser]

How cold is it out? Maybe try partially covering the grill?

 

[RonJon '06]

Does the 1998 have an air recirculater? On my '06 the hinge broke and the door dislodged blocking the air flow. Happened in the summer so the cab wouldn't cool down.

 

[ljwhite174]

@ NYCruiser its in the 20s but the engine temp has been like this for sometime now since i had the water pump changed about a year ago. @RonJon '06 i dont think the 98 does but it seem that the vaccum pump is not working i checked the pump and its not making any kind of signs of working, and the air coming out of the vents is luke warm at best i am starting to think maybe the heater core may be clogged.

 

[CKH]

Check the vacuum line on the passenger side near where it goes to the T by the rear of the valve cover. Could be a broken line, that plastic gets brittle and cracks easily. Also try changing your coolant temp sensor or hooking up another gauge to see it its one of the two not working properly. I just changed my sensor, my gauge was reading low until I changed the sensor.