A4(B8 Platform) Discussion - UK: diesel Running cold, bad thermostat? - Audi A4 B8 allroad 2009 2.0TDI Wont reach 90c under normal use, generally sits between 50-70C when driving, goes up whilst driving uphill and down when downhill. Will reach 90 when stationary, but drops as soon as you move off. Have already Hithere I recently bought a VCDS to troubleshoot a heating issue we have with our car (Audi A4 B8 8K 2014 Quattro). The car doesn't overheat, so I don't think it is the water pump (although my mechanic mate reckons they tend to fail quite a bit). I think it could be the heater control valve Lowcoolant level. One of the primary reasons for engine overheating in A4 is a low level of coolant or antifreeze in the cooling system. Coolant plays a critical role in regulating the engine’s temperature by dissipating heat. When the coolant level is low, there is not enough fluid to absorb and transfer heat away from the engine. Theprice of car parts within the category Coolant thermostat for A4 B8 ranges from £7 to £55, depending on the manufacturer and product specifications. Top AUDI models: Coolant thermostat A3, Thermostat A6, Coolant thermostat A5, Thermostat TT, Coolant thermostat A1, Top Automaker: Coolant thermostat BMW, Thermostat VW, Coolant Original thermostat was replaced under the recall/service action at 8K miles, car now has 81K) News Home; Industry News '10 B8 S4 6MT, 09 B8 A4, 06 S4 6MT, 07 A4 6MT, 02 A4 QM, 99 A4 QM. 09-16 need to argue with the dealer and Audi of America about this because the thermostat on the new S4's are known for a bad failure TheB8 A4 lineup included a sedan, an Avant/wagon, an Allroad Quattro (4WD), and a sedan explicitly tailored to the Chinese market (the A4L). Different external and internal components of the B8 were updated in 2012. The 2.0L TFSI and 1.8L TFSI were the most common gasoline engines in the A4 B8, while the 2.0L TDI was the most Forreference this was the car's original thermostat, 97kmi. So in short: -Yes, the 1.8T thermostat can stick closed. -If'n you have no heat in the cabin and the car is overheating it is probably the waterpump. -If'n you have heat in the cabin and the car is overheating it is probably the thermostat. -Buy the dipstick tube with the thermostat Hi I have changed thermostat for 3.0 TDI, you can order it separately, but not directly from VW/Audi but as a replacement part. It is easy to test, if you are unsure if it is faulty, but it is hard to reach. I will look up for part no, I have it written down. EDIT: I found part no for 2.0 TDi, it is 1K0 121 113A. S4bH3L.