DIY thermostat swap

[R55ENS]

Has anyone attempted to do this themselves? And was it a nightmare of a job?

My water temp keeps shooting up to 110c and I get the 'max engine revs 6000rpm' warning on the dash aswell.

Need to get this sorted so I can sell it in good faith! Not what I needed right now!

[R55ENS]

Managed to swap it out yesterday. Went alot easier than I thought. All though it took 1.5 hrs to just get one rusted bolt out!! Mainly due to the lack of access to it.

Everything seems to be working as it should now!

[Dr.Digga]

I have the exact same problem.
Running the car on the Autobahn at a steady 120kmph will cause the temp gauge to rise at some point and cause the 6000rpm warning. Continuing to drive in the same fashion will cause the temp gauge to rise up until a bit above 110°, but then go down to the normal 90° after about 1 minute/30 seconds. Was that the same with you? If not, what else could cause this? Waterpump?

Anything I would have to watch out for when replacing the thermostat? I assume it is straight forward in terms of removing engine cover, electric plugs to thermostat (if any), removing hoses, thermostat out and same thing in reverse?

[Grandadg90]

My light came on the other day, 'don't exceed 6k rpm'. Cars temperature is normal, but as a precaution o haven't driven the car since. I have booked her in at my local specislist. The cars fan runs momenterily after switch off. Will get the cars diagnostics read, but is the general consensus that it will be the thermostat or the thermostat sensor?

Any help will be appreciated.

[SteffRS4]

Hi Bud.
I had the same issue as yourself and it turned out to be the thermostat, while it was in they struggled with a couple of the bolts to remove it from the water pump, so I got them to replace that at the same time while it was in there an striped, haven’t had any issues with it since

[Grandadg90]

So update on my RS. No codes found in the diagnostics.

How can we possibly check to see if it is the thermostat. Is there a water temperature test that can be carried out.

[TheBigFish]

Hi guys, maybe you can help me please? I've had a 2014 RS4 for a few months and since buying it its had the following fault:

8113 - Performance Malfunction in Cooling System
P2181 00 [237] - -
MIL ON - Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 4
Mileage: 76238 km
Date: 2022.10.30
Time: 17:24:00

Engine RPM: 2385.00 /min
Normed load value: 24.7 %
Vehicle speed: 57 km/h
Coolant temperature: 66 °C
Intake air temperature: 29 °C
Ambient air pressure: 990 mbar
Voltage terminal 30: 14.182 V
Unlearning counter according OBD: 40

I also had an invcident yesterday misfiring and juddery, I thought the engine was going to cut out. The 600rpm thing came up on the dash board as mentioned in your posts above. Also the follwing codes:

16811 - Fuel Trim; Bank 1
P0171 00 [096] - System Too Lean
Intermittent - Not Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 1
Mileage: 77886 km
Date: 2022.12.03
Time: 10:55:40

Engine RPM: 1975.50 /min
Normed load value: 47.5 %
Vehicle speed: 64 km/h
Coolant temperature: 78 °C
Intake air temperature: 26 °C
Ambient air pressure: 1010 mbar
Voltage terminal 30: 14.442 V
Unlearning counter according OBD: 24
CAN status - engine control module-Bits 0-7: 0
CAN status - transmission control module-Bits 0-7: 0
CAN status - brake control module 1-Bits 0-7: 0
CAN status - brake control module 2-Bits 0-7: 0
selected gear-Bits 0-7: 6
Cruise control switch actuation-Bits 0-7: 0
Cruise control switch actuation-Bits 0-7: 0

2838 - Fuel Rail/System Pressure
P0087 00 [101] - Too Low
Not Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 1
Mileage: 79049 km
Date: 2022.12.29
Time: 08:49:26

Engine RPM: 2112.50 /min
Normed load value: 87.5 %
Vehicle speed: 75 km/h
Coolant temperature: 46 °C
Intake air temperature: 11 °C
Ambient air pressure: 970 mbar
Voltage terminal 30: 14.277 V
Unlearning counter according OBD: 40
Engine status-Bits 0-7: 3
Engine oil temperature: 42.6 °C
Engine operating condition: Part throttle
Engine operating condition-Test_Program_Channel 87: 6

17895 - Valve for High-Pressure Fuel Pump
P12A3 00 [100] - Stuck Open
Intermittent - Not Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 2
Mileage: 79051 km
Date: 2022.12.29
Time: 08:51:04

Engine RPM: 1385.50 /min
Normed load value: 82.7 %
Vehicle speed: 35 km/h
Coolant temperature: 56 °C
Intake air temperature: 13 °C
Ambient air pressure: 970 mbar
Voltage terminal 30: 14.277 V
Unlearning counter according OBD: 40
Engine status-Bits 0-7: 3
Engine oil temperature: 47.0 °C
Engine operating condition: Part throttle
Engine operating condition-Test_Program_Channel 87: 6

17899 - Fuel Rail/System Pressure
P0087 00 [100] - Too Low
Intermittent - Not Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 1
Mileage: 79051 km
Date: 2022.12.29
Time: 08:51:58

Engine RPM: 1279.50 /min
Normed load value: 89.0 %
Vehicle speed: 0 km/h
Coolant temperature: 53 °C
Intake air temperature: 14 °C
Ambient air pressure: 970 mbar
Voltage terminal 30: 12.910 V
Unlearning counter according OBD: 40
Engine status-Bits 0-7: 3
Engine oil temperature: 50.6 °C
Engine operating condition: Part throttle
Engine operating condition-Test_Program_Channel 87: 6

7697 - Oxygen (Lambda) Sensor B2 S1 Voltage too Low / Air Leakage / Sample Error
P2415 00 [101] - -
Not Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 1
Mileage: 79051 km
Date: 2022.12.29
Time: 08:51:31

Engine RPM: 986.50 /min
Normed load value: 16.1 %
Vehicle speed: 25 km/h
Coolant temperature: 54 °C
Intake air temperature: 11 °C
Ambient air pressure: 970 mbar
Voltage terminal 30: 14.418 V
Unlearning counter according OBD: 40
Engine status-Bits 0-7: 3
Engine oil temperature: 47.8 °C
Engine operating condition: Idle
Engine operating condition-Test_Program_Channel 87: 5
Driver-side belt buckle status-Bits 0-7: 62
Current system status: SYC_DRIVE
Current system status-Test_Program_Exe Con State 02 UBYTE: 4

7683 - Oxygen (Lambda) Sensor B1 S1 Voltage too Low / Air Leakage / Sample Error
P2414 00 [101] - -
Not Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 1
Mileage: 79051 km
Date: 2022.12.29
Time: 08:51:31

Engine RPM: 990.50 /min
Normed load value: 16.1 %
Vehicle speed: 25 km/h
Coolant temperature: 54 °C
Intake air temperature: 11 °C
Ambient air pressure: 970 mbar
Voltage terminal 30: 14.418 V
Unlearning counter according OBD: 40
Engine status-Bits 0-7: 3
Engine oil temperature: 47.8 °C
Engine operating condition: Idle
Engine operating condition-Test_Program_Channel 87: 5
Driver-side belt buckle status-Bits 0-7: 61
Current system status: SYC_DRIVE
Current system status-Test_Program_Exe Con State 02 UBYTE: 4


Readiness: 0000 0000


I think I have 2 separate problems here, one is coolant temperature related and opne is fuelling related. My thoughts are a failed thermostat and potentiallyt a failing HP pump. I dont understand why the 6000rpm fault came up as the engine speed was more like 2500rpm. Does anyone know? Also, the car always seems to run at low temperature, I' suspecting a stuck open thermostat. Do I need to take the bumper and radiator off to replace this? Any pointers in the right direction woudl be greatly appreciated before I get the spanners out