Engine coolant temp sensor

[roba4cab]

Easy fix? Any links with pics of location would be great? Any help would be much appreciated. Thanks

[white.akita]

Which engine!

[roba4cab]

Cab 1.8t thanks

[quattrojames]

Coolant Temperature Sensor Replacement Guide

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[pauldazzle]

Can't say I'm too impressed with that guide. Cheap CTS. Use a genuine green VAG CTS as aftermarket, & Ebay ones are notoriously unreliable. (CTS has 2 outputs feeds 1 to the temp guage & the other to the ECU a fault on the CTS ECU output will cause incorrect fueling & running issues).

It's an easy 5 minute job to do on a 1.8 T VW/ Seat?Skoda as they're tranverse, but a little bit more of a pain on Audi as access is tight. Took me less than 10 mins on my Audi A4 TDI though.
On the Audi 1.8T CTS is located at the rear of the engine.
The CTS is held in place by a plastic C clip which in the above guide had maybe been fitted on the wrong side of the CTS housing, which is why he had so much trouble removing it, but as he advised it's worth having a spare c clip on hand.

Obviously do the job with the engine cold.
Leave the header tank cap on as it reduces the ammount of coolant loss. Have the new CTS with a new O ring fitted ready to install. Pull the C clip out & pull the CTS up out of it's housing, the O ring usually doesn't come out with it so be ready to dig it out. Put the new CTS in & replace the C clip. Then disconnect the connector of the old CTS ( it's easier to get off with the CTS out), & refit to the new one. Top up the header tank with G12, & check that the CTS has seated properly & not leaking. With header tank cap off & the heater on full hot start the engine & bring it up to temp holding the RPM's up at 2500 until the temp gauge has sat at 90 for a few minutes. Then check coolant level & top up if neccesary. It's important to do this last part to remove any air locks in the coolant system.