Recommended replacement interval for the part category Thermostat : 50000 km

Important!

This replacement procedure can be used for:
VW Golf VI Variant (AJ5) 2.0 TDI, VW Golf VI Variant (AJ5) 2.0 TDI … View more

The steps may slightly vary depending on the car design.

This video shows the replacement procedure of a similar car part on another vehicle

Alternative products

Thermostat

Replacement: engine thermostat – VW GOLF VI Variant (AJ5). Tools you might need:

                      Wire brush
                    
                      All-purpose cleaning spray
                    
                      Sealant
                    
                      Torque wrench
                    
                      Combination spanner #10
                    
                      Drive socket # 7 
                    
                      Drive socket # 10 
                    
                      XZN socket bit # 6
                    
                      Torx bit T27
                    
                      Ratchet wrench
                    
                      Funnel
                    
                      Clic-R collar pliers
                    
                      Needle nose pliers
                    
                      Fluid container
                    
                      Microfibre towel
                    
                      Fender cover

Buy tools

Replacement: engine thermostat – VW GOLF VI Variant (AJ5). Professionals recommend:

Check the condition of the coolant every time you replace the thermostat. Change the coolant if necessary.
Please note: all work on the car – VW GOLF VI Variant (AJ5) – should be done with the engine switched off.
All work should be done with the engine stopped.

Carry out replacement in the following order:

Step 1

Open the hood.

Step 2

Use a fender protection cover to prevent damaging paintwork and plastic parts of the car.
Step 3

Remove the air duct.
Step 4

Clean the throttle body fasteners. Use all-purpose cleaning spray.
Step 5

Disconnect the throttle body connector.
Step 6

Loosen the fastener of the air intake hose. Use a drive socket #7. Use a ratchet wrench.
Step 7

Unscrew the dipstick tube fastener. Use a drive socket #10. Use a ratchet wrench.
Step 8

Loosen the fastener of the air intake hose. Use a drive socket #7. Use a ratchet wrench.

Step 9

Remove the air intake duct.
Step 10

Cover the air intake hose with a microfibre towel to prevent dust and dirt from getting into the system.
Step 11

Unscrew the fasteners connecting the throttle valve to the intake manifold. Use Torx T27. Use a ratchet wrench.
Step 12

Remove the fastening bolts.
Step 13

Detach the throttle body from the intake manifold.

Replacement: engine thermostat – VW GOLF VI Variant (AJ5). AUTODOC experts recommend:
Clean the throttle body if necessary.
Step 14

Unscrew the coolant reservoir cap.
Step 15

Lift the car using a jack or place it over an inspection pit.

Step 16

Clean the coolant hose. Use all-purpose cleaning spray.
Step 17

Prepare a container for fluids.
Step 18

Loosen the coolant hose clamp. Use clic-R collar pliers.
Step 19

Detach the coolant hose.
Step 20

Drain the coolant from the engine.

Replacement: engine thermostat – VW GOLF VI Variant (AJ5). Tip:
Caution! The coolant can be very hot.Wear gloves to prevent contact with hot liquid.Wait until the coolant has completely flowed out of the drain hole.
Step 21

Clean the coolant hose. Use all-purpose cleaning spray.
Step 22

Attach the coolant hose.
Step 23

Secure the coolant hose clamp. Use clic-R collar pliers.
Step 24

Lower the car.

Step 25

Prepare a container for fluids.

Step 26

Detach the clamp of the upper coolant hose. Use clic-R collar pliers.
Step 27

Detach the upper coolant hose.

Replacement: engine thermostat – VW GOLF VI Variant (AJ5). Tip from AUTODOC:
Caution! Coolant may leak out of the coolant lines and thermostat housing.
Step 28

Detach the clamp of the upper coolant hose. Use needle nose pliers.
Step 29

Detach the upper coolant hose.

Replacement: engine thermostat – VW GOLF VI Variant (AJ5). Tip:
Caution! Coolant may leak out of the coolant lines and thermostat housing.
Step 30

Detach the clamp of the upper coolant hose. Use needle nose pliers.
Step 31

Detach the upper coolant hose.

Replacement: engine thermostat – VW GOLF VI Variant (AJ5). Tip from AUTODOC:
Caution! Coolant may leak out of the coolant lines and thermostat housing.
Step 32

Detach the clamp of the upper coolant hose. Use clic-R collar pliers.
Step 33

Detach the upper coolant hose.

Replacement: engine thermostat – VW GOLF VI Variant (AJ5). AUTODOC experts recommend:
Caution! Coolant may leak out of the coolant lines and thermostat housing.
Step 34

Unscrew the fastener of the coolant hose clamp. Use XZN #6. Use a ratchet wrench.
Step 35

Clean the thermostat housing. Use all-purpose cleaning spray.
Step 36

Unscrew the thermostat housing fasteners. Use a drive socket #10. Use a ratchet wrench.
Step 37

Remove the fastening bolts.
Step 38

Remove the thermostat housing together with the thermostat.

AUTODOC recommends:
Replacement: engine thermostat – VW GOLF VI Variant (AJ5). Do not use excessive force when removing the part as this may damage it.
Step 39

Clean the thermostat housing mounting seat. Use a wire brush. Use all-purpose cleaning spray.
Step 40

Install the new thermostat housing together with the thermostat.

AUTODOC recommends:
Replacement: engine thermostat – VW GOLF VI Variant (AJ5). Do not use excessive force during installation. This may damage the part.
Step 41

Treat the fastening bolts. Use a sealant.
Step 42

Install the fastening bolts.
Step 43

Tighten the thermostat housing fasteners. Use a drive socket #10. Use a torque wrench. Tighten it to 9 nm torque.
Step 44

Attach the upper coolant hose.
Step 45

Attach the clamp of the upper coolant hose. Use needle nose pliers.
Step 46

Screw in the fastener of the coolant hose clamp. Use XZN #6. Use a torque wrench. Tighten it to 7 nm torque.
Step 47

Attach the upper coolant hose.
Step 48

Attach the clamp of the upper coolant hose. Use clic-R collar pliers.
Step 49

Attach the upper coolant hose.
Step 50

Attach the clamp of the upper coolant hose. Use clic-R collar pliers.
Step 51

Attach the upper coolant hose.

Step 52

Attach the clamp of the upper coolant hose. Use needle nose pliers.

Step 53

Treat the fastening bolts. Use a sealant.
Step 54

Clean the throttle body mounting seats. Use all-purpose cleaning spray.
Step 55

Install the throttle valve on the intake manifold. Install the fastening bolts.
Step 56

Tighten the throttle body fasteners to the air intake manifold. Use Torx T27. Use a torque wrench. Tighten it to 14 nm torque.
Step 57

Remove the microfibre towel from the air intake hose.
Step 58

Clean the mounting seat of the air intake hose. Use all-purpose cleaning spray.
Step 59

Reinstall the air intake duct.
Step 60

Screw in the dipstick tube fastener. Use a combination spanner #10.
Step 61

Secure the fastener of the air intake duct. Use a drive socket #7. Use a ratchet wrench.
Step 62

Connect the throttle body connector.
Step 63

Install the air duct.
Step 64

Remove the coolant reservoir cap.
Step 65

Insert the funnel.
Step 66

Pour coolant in the coolant reservoir.

Replacement: engine thermostat – VW GOLF VI Variant (AJ5). Tip from AUTODOC:
Only use the coolant recommended by the manufacturer.The coolant level should be at the MAX mark.Wait until the air goes out of the system.
Step 67

Run the engine for a few minutes. This should be done in order to remove residual air from the cooling system and to check if the components are operating correctly.
Step 68

Shut off the engine.

Step 69

Check the coolant level. If necessary, top up to the required level.
Step 70

Install the coolant reservoir cap.
Step 71

Screw on the coolant reservoir cap.
Step 72

Remove the fender protection cover.

Step 73

Close the hood.

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