Possible stuck thermostat...

[JusteR]

It sounds like the radiator is getting hot but the water isn't circulating through the radiator and back to the engine.

fixed it for you

[JusteR]

Those of you who work on VW's may remember the 2.0 and plastic water pump impellers. Here's a crosspost that may be helpful as it develops.

VWVortex.com - Temperature gauge reads hot when the engine is not overheating

*Flame suit on*

[Pickles]

Ok, got everything replaced, now im HOPING the only problem is air in the system... Burped it as best as I could...
Currently, the car idles fine, perfect temp, fan comes on when it should etc.
When driving the temp will jump to 220 and the coolant will overflow. When I stop at a light/sign/ whatever it jumps back down to 190... my mechanic tells me this may be a bad head gasket... no white smoke, no oil in coolant, no coolant in oil... so im thinking otherwise...any suggestions?

[Pickles]

would letting it sit and idle help with burping?

[avguy]

My experience with the '05 and '06 is that they burp very easily, without even raising the front-end way up. So, unless they changed the rad in the '10, I don't think that's your problem. JusteR already mentioned the block combustion gas test, which any decent shop can do (or you can buy/rent the tester and do it yourself). If no combustion gas shows up in the test, it wouldn't guarantee that you don't have a bad HG, but a positive gas test would unfortunately confirm bad news. I'm really puzzled that you're having problems like this on a fairly new vehicle - how many miles on it? Did you have anything else happen in the recent past that might explain this problem? Of course there can always be a bad part or factory assembly. Do you still have a drivetrain warranty?

[Thymeclock]

fixed it for you

Um... no, not for me, as it's not my problem.

Still gotta fix the problem for the OP, don't we?
.

[Thymeclock]

Those of you who work on VW's may remember the 2.0 and plastic water pump impellers. Here's a crosspost that may be helpful as it develops.

VWVortex.com - Temperature gauge reads hot when the engine is not overheating

*Flame suit on*

No disagreement, as it could very well be the problem. I had a Fiat once that had to be bled (burped) at the very top of the engine block once the system was opened and air was present in it. Actually the easiest way to do it was to fill it with fluid at that highest point.

[Pickles]

My experience with the '05 and '06 is that they burp very easily, without even raising the front-end way up. So, unless they changed the rad in the '10, I don't think that's your problem. JusteR already mentioned the block combustion gas test, which any decent shop can do (or you can buy/rent the tester and do it yourself). If no combustion gas shows up in the test, it wouldn't guarantee that you don't have a bad HG, but a positive gas test would unfortunately confirm bad news. I'm really puzzled that you're having problems like this on a fairly new vehicle - how many miles on it? Did you have anything else happen in the recent past that might explain this problem? Of course there can always be a bad part or factory assembly. Do you still have a drivetrain warranty?

I still have drive train warranty, so that's a plus... I don't know why I am having this problem either... the car is a 2010 with about 36500 miles

[avguy]

I still have drive train warranty, so that's a plus...

Was yesterday's t-stat work done by a dealer? How about oil changes? No first-hand experience myself, but I've read accounts where they tried to use ANY excuse to do the dealer dance and deny the claim.

[Pickles]

Was yesterday's t-stat work done by a dealer? How about oil changes? No first-hand experience myself, but I've read accounts where they tried to use ANY excuse to do the dealer dance and deny the claim.

Well, I know it isnt the head gasket... although something interesting... pulled the T-stat out of the old housing and everything.. its marked 105*... does that mean 221*f?! That is an insanely high temp for a tstat..