Hello all. I recently started having an issue with my 96 Ram 1500, and not a good one with this cold weather. What ive noticed is at idle my heater is barely putting out if any warm air, when running it for a while (20+ minutes) its warm but not exactly hot. Earlier today I was idling in a parking lot and I was watching my temp gauge go up when idling, and would go back down to normal if i revved a bit plus a gurgling sound when I revved. Its not overheating what I mean by that is its running warm but not reaching the red line. I see no coolant leaks, just put in a new radiator and hoses this summer, also havnt noticed anything leaking in the cab. Although I did notice a frosty inside windshield the other morning. So my question is should I be checking the thermostat, heater core ( I see no leaks but could have sworn I smelled coolant the other day) or could it be something else. Thanks for any input.

 

Sounds like you have air trapped in your heater core. Pretty common in these trucks. Need to get that air burped out. If you smelt coolant try to find the leak. If the heater core is leaking that would cause an air bubble in it. If the truck is getting up to operating temp at a normal rate odds are its working fine.

 

If it warmed up while idling, I think your water pump is bad. It's not properly circulating the coolant. That explains the warming at idle and lack of heat.

 

^x2

And, you may still have a pinhole in your heater core. Start with the pump though (and thermostat, don't forget to drill the hole too).

 

Thanks guys I'll check that out, appreciate the replies