2.5 tdi temperature problem


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May 18, 2012
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Hi guys I know this question has been asked a thousand times but I can't find much info on the 2.5 tdi engine code ake my temp gauge only ever reaches 70 degrees so I'm going to replace the thermostat and temp sensor is there a guide anywhere for doing this on a 2.5 ? Also would this cause problems with starting the car when it's warm ? When it's cold it starts fine with no issues but when it's been driven and heated up and turned off for about an hour it's very difficult to start I think that because the temperature gauge is faulty its messing up the air fuel mixture when starting would this be correct also I seem to have poor mpg top would this be another problem caused by the temp sensor ?
Poor mpg can be caused by both a temp sensor and the thermostat.

Thermostat on the 2.5 is not an easy job. It's behind one of the cam shaft sprockets. So it's worth doing the cambelt at the same time.

As for the sensor. Lift the engine cover off and it's inbetween the V on the left of the engine at the front. It's green. There is a how to guide on here.
Am I right that this could cause the difficult starting too ?
Sounds like the CTS is the first port of call, as mentioned the thermostat is a job which requires new timing gear too.

I have done a write up on the CTS, it's in the DIY guides sticky thread.
Yep CTS first. Use a genuine VAG CTS only. Cheap aftermarket ones are very unreliable.
Cheers lads I was on to Audi this morning the have the cts in stock so I'll pick it up today and see how that goes as for the thermostat , timing belt is on the list of things to be done so when I'm getting it done I'll change the stat