Run VCDS on it & see what isn't working. Could be a fan issue or a false reading from one of the temp senders. What exactly does "pegs out hot" mean? The temp gauge rises then falls?

Mileage?

 

What I mean is the car gets hot, over heats, goes into red at 280. The car has 127k miles.

 

VCDS is the first thing as it avoids the guesswork. It could be a sensor it could be the ECM. This YT is interesting. Turned out , after replacing sensors & tearing their hair out to be dry joints on the ECM pcb. I would most likely start with a new thermostat & take it from there unless VCDS was forthcoming.

Any DIY on a Touareg needs access to VCDS unless you want to just throw parts at it & hope.

Is the VW Touareg a LEMON? (Crazy Overheating Issue!) - YouTube

 

Funny you say that! Was hoping it would not be the ECM but kind gathered it very well could be. I’ve replaced the thermostat..pretty much anything to do with cooling was replaced..

 

if the gauge is the only indication that it's over heating id take an infrared gun to the engine to confirm that's actually what's happening ?
280 is well past boiling temp even in a pressurized system w 50% coolant.

 

Where should the temp be measured with a temp gun exactly?

 

Typically when this happens, the AC fan isn't kicking on to help disperse the additional heat. Confirm by looking underhood and see if fan kicks on with AC turning on. Though, as Jeff said, 280* is HOT and would cause imminent damage. It could potentially be a funky reading.

Come back with vagcom scan.

 

Radiator, large coolant hoses, tstat housing...any # of places that carry coolant. If it's running that hot you'll see red flags somewhere.

 

What work\fixing has been recently done? Did you check coolant level both when cold and when overheating?

 

Hi All - thanks so much for the help. I got sick of all the issues and ended up trading the vehicle in when a dealer offered a great price fort the trade.