a4 over cooling ?

[sbt]

hi i have recently returned to audi after a few years break . i recently bought an audi a4 13 reg 2.0 177 ps black edition quattro avant lovely car drives great all except for one thing it seems to be over cooling the temp never gets to 90c even flying down the motorway it sits just under when i slow in traffic the temp drops and fluctuates if i turn the heating down it rises if i turn it back up the temp drops . The last audi diesel i owned was a 1.9tdi so i was just wondering if this is a trait of modern diesels or have i got an issue . ny advice would be appreciated

[philipharmes]

If it's got the DSG box, get the DSG cooler thermostat checked, it will probably be stuck open.

This then allows the engine coolant to by-pass the main thermostat through the DSG thermostat, this overcools the coolant & keeps the coolant temperature low.

[sbt]

Hi sorry forgot to mention it is a manual gearbox . do these just have the one main thermostat cheers

[philipharmes]

Yes, just the one thermostat at the bottom of the engine if it's manual.

Sounds like it is partially stuck open or opening at too lower a temperature, so needs replacing.

[sbt]

hi ll sorted now after my trip to awesome gti they fitted a new thermostat with the timing belt and water pump kit it gets up to temp pritty quick now and stays there thankfully was not looking forward to winter with no heating . so for all those people saying it is normal for a diesel in winter well its not get your thermostat changed

[quattrogary]

Morning
Just bought similar car,what sort of mpg are you getting?
Mines in next week for a knackered thermostat,wont even get to 70 degrees
Thanks

[sbt]

HI i came from a 1.6tdci transit connect van so the mpg does seem poor . i do not keep tabs on mpg but i do know that doing the exact same journey to work i am filling it up two days earlier than i did in the van so not happy i appreciate it is a 2.0 and the van was a 1.6 but i must admit i did expect better from an audi diesel as regards the temp issue even with a brand new genuine thermostat in it still takes a while to fully warm up and if you have the heater on high it will struggle to hold temp especially if the outside temp is cold but i suppose this is the price you have to pay for a supposedly efficient diesel engine its just in this case it is not as efficient as i was led to expect . all that said its a great car which i will be keeping for a good while i suppose 177bhp and quattro does not come cheap i could of kept the van but the 1.6 tdci ford engine whilst efficient was the biggest bag of gutless garbage i have ever had in a vehicle and was over the moon to see it drive away

[quattrogary]

I did expect better mpg,my a6 2.7tdi was more fuel efficient
In the garage next week for new stat+ inspection. If mpg issue not rectified,wont be keeping very long.
Shame,my last audi was great.

[sbt]

Same here i had a 1.9tdi a4 avant a good while back had it remapped to 170 bhp fantastic car and virtually run on thin air . it would appear despite audi's claims of mpg that they are going backwards how they get away with their reported mpg figures god only knows reading other posts on here i know a hell of a lot of people are not happy and i dont blame them

[sbt]

Hi all as an after thought as anyone had an economy remap on any audi diesel where it made a significant difference to the MPG . i have been thinking this over for a while but unless there is a significant improvement and can not warrant the outlay for the remap