It would depend on if the thermo was stuck open or closed.

 

Ok, I spoke to the mechanic directly at the dealership. They called Audi with all the details and they're suggesting the head gasket replacement. The mechanic said he had a similar issue a few years ago. Basically there was a weird pressure issue that caused air to get sucked in without fluid leaking out of the engine. He had a special tool/toolkit (not sure what) that involved putting a chemical into the coolant system that changes colors if combustable material is present. But then he said he did the same test on my car and it didn't show up. So I don't get it.

He said he can get all the air out of the system by bleeding at the heater core AND the radiator at the same time. Then heat gradually gets back in. He said he's replaced the block plug twice and can't think of anywhere else air could be getting in.

This is craziness...

 

I have the exact smae issue... I have replaced about the exact same components, too. Next I want to look into the mix door/blend door; where is it? Also, is it vacuum or electric actuated?

Is the cabin temp sensor on the dash by the defrost vents?

 

Please tell me the dealership did the TSB where they replaced the little coolant O-ring for the plug under the intake manifold? The TSB for this very same problem which costs a total of $3. God dealership technicians these days are idiots.

 

Have the same problem, engine at temperature but cab can not get very high temp. Also AC sma eproblem but does not get that cool.

Audi advised today they feel it is a plugged core from sediments????
$1500 to remove dash and replace core.. No warranty coverage.

I will ask re the tsb and if thye updated all, also if they back flushed as they put new hoses on and flushed a few months back to try and correct the problem.

Here is a tsb link, http://www.allworldauto.com/tsbs/ is it 10015099 in the engine cooling section?


Thanks,

 

I saw an interesting blog about the same situation on an A4 while researching this problem on my sons A4. this guy describes the whole dealership issues and TS they did and finally decides to fix it himself. The heater core has an upper and lower section, and the only real way to tell if the whole thing is seeing fluid is to take an IR temp reding on the core with the car running, if the power half of the core is not hot, then that part is clogged. The sucky part is they can flush it all they want, but won't get teh clog. What he did was to take the hoses of at the firewall and connect tubing from the core to 2l plastic soda bottles filled 2/3 full with boiling water and CLR, then force the air and water back and forth between the bottles. The description is in post #51 at http://www.advrider.com/forums/showt...=411979&page=4. I am going to try this on my next day off.

 

Hi!
I have the same problem..i get a slight bit of heat from the windshield but cool air from the heater area near my feet.a
The Audi dealership is telling me that they cannot reverse flush the heater core
They said the coolant only flows one way
Any thoughts?

 

This a common problem on Audis and has been for years. Had the same issue. Kept contemplating ripping the dash apart and changing the heater core. Also kept thinking I should replace the thermostat. IT'S A BLEEDING ISSUE. If you run the car to operating temp and pull the heater core inlet hose off, you will NOT, have a steady flow of coolant. You need to bleed the core at the inlet hose. Sometimes it takes holding the accelerator down at about 2500 rpm for approx. 15 mintues before you will even see a flow of coolant come up through there. It's the way this system is designed. The heater core is basically a bypass with a slow moving low pressure of coolant flowing through it. Trust me and don't give up. Bleed over and over again and can take a lot of time in most cases. There is a great DIY on Audizine that I went by and got mine to work. I'll try and find it and put up a link.

 

I traded it in on a new volvo. heat works great. Will never own a audi again.

 

Good luck...