2001 Leon Cupra overcooling

[Roadster25]

Gentlemen,

My Leon Cupra has a habit of running a bit cold, unless stuck in traffic or making particularly good progress.

Initial thoughts were thermostat failure, but this has been checked and seems to be OK. There are no other signs of any engine problems.

I do run with the a/c on and set to automatic almost all of the time, as suggested in the handbook. Is the a/c fan likely to be causing the overcooling? It does appear to be on all of the time.

Should it be doing this, or is there a fault there?

Any thoughts or guidance, apart from "switch off the a/c ?

Thanks

[cuprabob]

With the air con on the fan should run on low speed, so you don't have a fault there. In fact it's very common for the resistor on the low speed circuit within the fan to fail making it not run. So you are very lucky in that respect.

Engine Coolant Temperature (ECT) sensor is a common faulure so that could be giving false readings.

[Cupramax]

Roadster25 said:

Initial thoughts were thermostat failure, but this has been checked and seems to be OK. There are no other signs of any engine problems.

That would have been mine too, have you actually put a new one in, theyre less than a tenner at Euro car parts.

[Roadster25]

Thinking about it, I have no idea how the garage decided the thermostat was OK. Having had a look at it yesterday I can see why they tried to suggest another problem - looks like an absolute pig to get to. I'm ashamed to say it looks like a job for someone else to me too

I don't think it is a sensor issues because when the temperature guage goes down the heater also runs out of puff.

Thanks for your thoughts chaps.

[Roadster25]

Thermostat now changed, problem solved.