No heat after Radiator Flush

I had my radiator flushed this summer (At the local Toyota Dealer) and now that its getting cooler I tried the heat, it blows cold at idle and if you rev the motor it warms up a little, driving is a little better, I put a thermometer in the vent and at Idle its 69 degrees full heat ,driving, it increases to 100. I live in the Midwest and that wont cut it. I have 125000 miles on the truck. Prior to the flush I had no problems. I back flushed the heater core and it was clear and no restrictions. I just had a new Frame put under it due to the frame recall and they had to drain the radiator but there was still no change. Any advice would be appreciated. The inlet hose for the heater core is hot the exit hose is cool.

Thanks allot

 

is all the air out? maybe the heater control valve has crud in it from the flush so its not opening all the way please let us know how you made out

 

Do you know where the heater control valve is located ? I have it idling as I type with the radiator cap off to burp the system.

 

if you have a set of ramps put the truck up on them with the cap open. it should burp it out. keep filling rad as it does and dont get burned!! air goes to the highest point in the system.... works for me yotas and jeeps both

 

Yep already did that .....

 

Hmmm I remember my thermostat got stuck open when I had a dodge neon and I never had heated air coming through the vents. When I swapped out my thermostat for a new one my heater started working

Not sure if that makes sense.

 

Ive never seen it happen, but I suppose they could have pushed crud into the heater core. You might try flushing then backflushing the core. <shrug>

 

You have air in the system.

The above is a common indicator for air in the system.

 

Also a symptom of a stuck thermostat thats letting the rad fluid circulate when it shouldnt.

 

Yeah, but he just flushed and starting with the easy stuff first.

 

Where does the coolant temperature gauge sit during normal driving after warm-up? Normal is 1/2 way up or so, and continually running below that indicates a stuck-open thermostat. Normal reading would point to an air-lock, blockage, incorrect heater plumbing, or a blend-air door or actuator problem within the HVAC box. Since you say the inlet hose is hot, and the return is cold, that points to the first three.

 

My temp is normal,I can hear the blend door move when I adjust the temp. I took it back to the dealer and they say its the core and it needs replaced $ 1700.00. But I told them there was not any restrictions as I backed flushed the core and had good flow both directions. The plumbing is correct I verified it. I'm stumped. I tried raising the front of the truck to burp it but no change.

 

Bleed the heater core. Get the car running and drive the front wheels up on blocks, let it run while your doing this. One of the heater core hoses should have a pin hole in it by the very edge(sometimes has a white dot over the hole), with the car running undo the clamp for the hose with the hole from the pipe. Slowly Slide the hose back off the pipe(without pulling it off) untill the hole is off the pipe. Air and bubbles and some coolant will come out of the pin hole. When straight up stream of coolant is the only thing coming out of the hole, slide it back on the pipe, clamp it up and and check your heat.
Takes 1min.

 

What! I have never seen one like that.

 

It's pretty generic, maybe the Tacoma doesn't have the pin hole? Locate the outlet pipe and put a pin hole in it.

 

I would give steelhd's advise a shot. And then there's this:

http://www.lislecorp.com/divisions/products/?product=606&division=1&category=6

 

There must be air still trapped somewhere in the system.

 

Buy this product. Park the truck level or a little nose up. No need for ramps. The radiator cap is the highest point in the system. With the engine cold put on the funnel using the adapters with the kit. Fill the funnel about 3/4 full. Start the truck. Turn on the HVAC to full heat and highest speed on the fan. When the truck warms up the thermostat will open. When it does coolant from the funnel will then flow into the radiator. Be prepared to add more coolant to the funnel to keep more air from getting in the system. Check the heat inside the truck. Good shut off the truck. Put the stopper in the funnel. Remove funnel. Done!

 

normally this is a thermostat issue, but if every thing was fine before the flush i bet the coolant level is low. if the thermostat was not open when they were refilling to circulate into the engine block and heater core, it will appear to be full when it's not.

 

hey op and anyone else interested. I made this video for a friend of how to bleed the heater core on a vehicle. Its just what i explained in my post above. this is how you bleed a heater core for any vehicle its free its easy and its fast.

this is a pic of tacoma heater core plumbing. It does not have a pinhole in it yet but just slide the hose back off the pipe without pulling it off and put a pin hole in it. (id put it dead in the middle of that cross.

heres the video of the procedure