Engine Coolant Temperature Sensor 1 Circuit High

[sarah_a3]

I've been having an intermittant engine light on the dash so bought myself an OBD scanner and the code is P0118 Engine Coolant Temp Sensor 1 Circuit High. After finally getting around to it, I replaced the sensor last Friday and cleared the code thinking that would be the end of it. But no, yesterday and today the code is back.

Anyone have any ideas what it could be? Fuel economy seems the same as usual but I am noticing the car is idling slightly higher shortly after cold starting at 1000-1200 than the usual 900 ish. Its a 2004 2.0TDI Sport.

Any help much appreciated!

[STEWY L]

some have two sensors i believe,
regards,
stewy.

[djgilson]

Sarah_a3, can’t help with your problem, I’m afraid, but I notice you bought a code scanner. There seem to be dozens on the market, and the available reviews are very mixed. Can I ask which one you bought? where from? and would you recommend it? And did you get any further with the problem? Many thanks.

David Gilson

[rd1]

Hi Sarah,
bit late perhaps but yes there are two sensors for the coolant, one in the expansion chamber which is easy to change and complete unit is only about £16 I think. Unfortunately the other is down in the engine which I had the main dealer change for me and after the diagnostics it cost £175.00. It did cure the problem but appeared expensive so if you can do it yourself then it will be worth it.
good luck
Rob

[sarah_a3]

Hi David,
Sorry for the slow reply, I haven't logged in for a while. I bought an Autel Maxiscan MS509 which I researched on various websites before buying on ebay for about £60 as it was cheaper than other websites. I don't really have anything to compare it to as it's the first scanner I've used but works well on a few cars I've tried it on. It shows live data and freeze frame data from when a fault code is triggered. You can also record data whilst driving and download it to a laptop/computer afterwards. All in all I'm happy with it because Audi wanted £100 to scan it once for the fault code and I have this scanner to use whenever now as an alternative.

I'm still having the sensor problem though - want to change my thermostat next but having looked at the weekend the access to the housing is pretty impossible to get at.

Hope this helps.

Sarah