I've checked upper and lower hoses and both are hot. Temp is just below 210 like always. Heater was working at the beginning of winter.

Now I have very low heat an sometimes it is barely Luke warm.

When engine is shut off I hear a sound like dripping or running water from underneath engine toward front but don't see a leak.

4wd also just went out but that's now related as far as I know. Any advice?

 

Change your thermostat. that should help, if not you will need to flush your heater core. be sure to put in 195* thermostat.

 

I thought it was supposed to run around 210.

Thermostat was replaced less than a year ago. Why would it go out so quickly?

I thought if upper and lower hoses were both hot that the heater core didn't need flushing.

 

210 is perfect. I have had t-stats go bad in a week. To me it sounds like your heater core is clogged. check this out, give it a shot. worked great for me.

You could also have a blend door problem as well. My money is on the heater core being clogged.

 

Gonna do the flush tomorrow. Got nothing to lose and looks to be an inexpensive way to move forward.

 

let me know how you make out!

 

Started to flush and noticed a leak where it was once spliced. Tightened it up. We'll see tomorrow how it does. Either way I'm gonna replace the hose this weekend.

 

X2 on the core. Hows your coolant level?

 

It was a little low. Added about half a gallon. Still gonna flush the core just gonna do it this weekend when I change the hose.

 

keep us posted

 

Flushed (back flush) the heater core twice and still no heat. I fear it's the heater core. But I did notice that the air flow changes from vents to floor to no where depending on acceleration and such. Maybe a vacuum problem then?

 

i would agree, are the hoses from the heater core hot on both sides?

 

Yeah. Top and bottom are hot. It does have some heat. It's slightly warmer after the flush. I had local shop flush the core nut they didn't use chemicals.

 

if both hoses are hot then you are moving coolant through the core. maybe check the heater controls to make sure the blend door is move correctly. you had mensioned that it changes with throttle.

 

Correct. When I am accelerating, the air switches from one vent location to another. If I keep accelerating, then at some point it sounds like all the air is blowing inside the dash but doesn't come put any vent.