[redman]

Hi
Is your engine running cooler than usual ?, as that is the first classic sign of a stuck open thermostat.

I have only ever heard of this fault code, informing you of a stuck open stat on the astra h. Apparently the ecu compares the engine temp sensor value with the radiator temp sensor value. If both the values rise at the same rate it knows it is passing. The engine temp sensor will be around 100c while the radiator sensor at 15c before rising sharply, when working normally.
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[redman]

I’ve been quoted £60 with the trade discount for the part from Vaux. Any ideas where else I can get the right part from?

Make sure you buy genuine vx thermostat or oem parts. £ 60 is a fair price if you ask me. Is it the stat that has an internal heater element and comes as a complete housing. If it is that's why it is quite expensive.

Last time l had to replace a similar stat, I bought it from autovaux on line.

 

[redman]

Thanks for your reply. I managed to get a second hand one off a Z18XER for £15 and it’s fixed the problem. I will keep that autovaux in mind.

As I’m due to get my timing belt replaced soon.

Glad it was an easy and cheap fix for you