Slow warm up of diesel engine

[RodA]

My 2008 A3 diesel is taking about 7 miles before the temperature reaches 90 deg. C.

I know that diesels are slower warming than petrol models but is 7 miles normal?

I'm considering replacing the thermostat but any information on what's normal would be appreciated.

Rod

[STEWY L]

that's ok, perfectly normal--about 12-15 mins light driving,
regards,
stewy.

[mikeybutch]

Its not the miles but time it takes any more than 15 mins the stat may be dodgy.Does the heater kick in sooner?

[RodA]

No, the heater is slow to give heat through as well. Watching the temperature gauge it doesn't rise of the cold mark for the first 3-4 miles, about 5 minutes?

[Eshrules]

We are approaching winter, cold air + cold (heat efficient) diesel engine = a while to warm.

as long as the car warms within 15>20 minutes (dependant on the driving, stop/start isn't helpful in this instance) and maintains that temp, with the heater following around the same time, I'd not worry.

[alankru]

I'd agree, my diesel A3 is already starting to take a while to warm up in this colder weather. Mine takes about 15-20 minutes and 10 miles to heat up to 90 degrees at the moment. I have my climate control set to automatic and I notice that after about 5-10 minutes the fan speed increases and heat starts to come out.

[RodA]

This is the first winter with the A3, I was comparing it with my other car, a Honda CR-V diesel, which heats up much quicker.

The A3 doesn't have climate control, with the temperature on full heat it seams to take a long time to get heat through to the interior.

From the posts above it would appear this is normal, I was just concerned that a slow warm up normally means the engine is not running at maximum efficiency so you use more fuel.

Rod

[alankru]

You are right, your mpg will no doubt drop (I used to notice it - I'll have to see this winter). I am just careful not to give it any hard acceleration until it is warm.