[evolvingpowercat]

My 2006 Touareg gasoline powered V8 is throwing intermittent yellow check engine MFD lamp and my VAG-COM reads a single coolant temp fault code. Reset and don't see the check engine and code again for several weeks. I seem to remember that when warmed up the coolant temp gauge needle would point straight up at 12:00 position. Now when warmed up it reads about 30F cooler at about the 10:00 position.

Other Touareg 1 V8 owners - in cold weather ( outdoor temps of 20s or 30s F ) what does your coolant temp needle read once your beast is warmed up? I am wondering if I have thermostatic valve that is sticking open somewhere preventing the coolant reaching the "proper" temp (if there is such a thing).

Thanks,

Randy
Overland Park, KS USA
2006 Touareg V8, 55K Miles

 

[jmansfield04]

The exact same thing happened to my 04 V8. Temp would only get up to 180 degrees. Eventually got a message in the MFD and error code. Turned out the thermostat was bad. Had the timing belt, water pump and thermostat all replaced at the same time. Timing belt covers the thermostat housing and has to be removed to replace the tstat.

 

[copaz]

Right on 200, every time.

 

[jmansfield04]

New tstat = 200

 

[copaz]

By the way, I get the cooling CEL too, but since my temp always goes up to 200 and stays there, I assume that my thermostat must be OK.

 

[jmansfield04]

I get the cooling CEL too, but since my temp always goes up to 200 and stays there, I assume that my thermostat must be OK.

Mine was registering 180 with no CEL for a long time so I replaced the ECT sensors, $30 each. Didn't correct my issue, but could be your problem. There's one at the top back of the engine and another on the passenger side near the bottom of the radiator. They're held on with C clips and it isn't necessary to drain the coolant if your quick swapping them out. I only lost a few ounces.

 

[copaz]

Mine was registering 180 with no CEL for a long time so I replaced the ECT sensors, $30 each. Didn't correct my issue, but could be your problem. There's one at the top back of the engine and another on the passenger side near the bottom of the radiator. They're held on with C clips and it isn't necessary to drain the coolant if your quick swapping them out. I only lost a few ounces.

Thanks jmansfield - Gotta change my coolant anyway (was a Texas car with not enough protection in the coolant for MN). So this is the time to do both. Thanks for the suggestion!