A3 Coolant warning light on dash

[donerkebab]

Further to my cold start problems - having to hold down accelerator whilst turning ignition I am now getting coolant warning light on dash. This is everytime in the morning but once warm is fine. ie at my favorite times of the day lunchtime and hometime Have checked and coolant is kinda hovering near minimum level but thought it was the crap building on the sensor issue. Just wondering what are implications of low coolant - in the morning it seems to lag with very low power /acceleration until the coolant light goes off. Is it best to top up or flush and replace? Will nip down to Audi to get some G12 tomorrow

 

[Sandip]

Cold start problem and coolant low is the exactly what happened with my S3, top the coolant up with some G12 and keep an eye on it, the fact you have the cold start issue and now coolant loss could be the early signs of head gasket failure or like in my case a cracked head!

Get the expansion tank tested for hydrocarbons, rule out the HG now before you start spending money on things that don't need fixing

 

[1animal1]

new expansion tank, £13......

 

[donerkebab]

Cold start problem and coolant low is the exactly what happened with my S3, top the coolant up with some G12 and keep an eye on it, the fact you have the cold start issue and now coolant loss could be the early signs of head gasket failure or like in my case a cracked head!

Get the expansion tank tested for hydrocarbons, rule out the HG now before you start spending money on things that don't need fixing

Thanks for quick response - how do u test the expansion tank for hydrocarbons? Guess if its head gasket then its time to try a quick part ex.....

 

[s3dave]

Thanks for quick response - how do u test the expansion tank for hydrocarbons? Guess if its head gasket then its time to try a quick part ex.....

emissions probe at a garage that does mots

 

[Sandip]

Thanks for quick response - how do u test the expansion tank for hydrocarbons? Guess if its head gasket then its time to try a quick part ex.....

You can test it like Dave said but i found that when i had trouble starting it was because my plugs had moisture on them, it got that bad they were soaked in coolant eventually

 

[donerkebab]

Cool will top up with G12 see how that goes - MOT was passed back in June so hope not- whats best way to check plugs - are these just before engine cover?

 

[Sandip]

Assuming it's an 1.8T, the plugs are under the engine cover. When it struggles to start, don't start the car, remove the plugs one at a time and have a look for any moisture on them.

Get the expansion tank tested first, mine had a dodgy start for nearly 2years and it's only recently got so bad

 

[donerkebab]

OK topped up the G12 - has gone an off pink murky colour. Still doing the cold start problem and coolant alarm in the morning only. Also temp is hovering nearer to 100 mark rather than normal 90 solid....

 

[Sandip]

Is your coolant level going low? Sounds like possibly the waterpump or HG, maybe both lol

 

[donerkebab]

Sorry bit of update - coolant light now off even in the morning guess it mixing sorted out the sensors - do they check for coolant concentration/strength? However still get a lag/limp mode - at least a minute before I get any power - is this sign HG going?