Coolant warning

upthepoll

Hi all, audi a4 2006 1.9 diesel, this morning i was driving along and the coolant light started flashing, i thoight this was odd as i had only filled the coolant tank a week previous, i also seemed to be losing power over 60 mph....i pulled in, opened the bonnet and it sounded like the engine was still running even though i had switched it off, i opened the cap of the coolant tank and the coolant sprayed out so there was plenty of coolant in the tank....i switched the car back on and everything was fine, drove it for about another half hour to work, the light stayed off and the power was fine and when i pulled in at work and switched the engine off there was no sound.....this puzzles me, any ideas what may have happened? would it be dirt in the tank or something?

blade1

When you say you filled the coolant tank do you mean you filled it to the top?

Alanstrainor

The sound was the electric engine fan staying on to cool the engine which must have been very hot. Coolant is not something you should be filling really, if you have to put coolant in regularly that means you have a leak and you need to get it fixed. Also filling coolant isn't necessarily an easy process, the system will need to be bled as air can get in the system when it goes low. And it's never a terribly good idea to open the tank when it's warm anyway.

Best start looking for leaks and keep a close eye on your coolant levels (when engine is cool).

upthepoll

blade1 wrote: »

When you say you filled the coolant tank do you mean you filled it to the top?

no, last weekend i just filled it to the level

upthepoll

Alanstrainor wrote: »

The sound was the electric engine fan staying on to cool the engine which must have been very hot. Coolant is not something you should be filling really, if you have to put coolant in regularly that means you have a leak and you need to get it fixed. Also filling coolant isn't necessarily an easy process, the system will need to be bled as air can get in the system when it goes low. And it's never a terribly good idea to open the tank when it's warm anyway.

Best start looking for leaks and keep a close eye on your coolant levels (when engine is cool).

thanks, i appear to have a very small leak, the coolant level seems to drop over a few months
in terms of the electric fan staying on, any idea what would have caused the engine to get so hot and the coolant light come on even though the coolant level was high?

corks finest

Alanstrainor wrote: »

The sound was the electric engine fan staying on to cool the engine which must have been very hot. Coolant is not something you should be filling really, if you have to put coolant in regularly that means you have a leak and you need to get it fixed. Also filling coolant isn't necessarily an easy process, the system will need to be bled as air can get in the system when it goes low. And it's never a terribly good idea to open the tank when it's warm anyway.

Best start looking for leaks and keep a close eye on your coolant levels (when engine is cool).

Possible airlock also

upthepoll

corks finest wrote: »

Possible airlock also

thanks, ran it again for a while at lunchtime and it seemed fine

Alanstrainor

Looking at google, it seems there is a common failure in the expansion tank in these cars. The tank has a sensor which begins to fail by showing random low coolant errors on the dash. If you are only putting very small amounts of coolant in every once and a while, I would think it unlikely for there to be air in the system. This seems like a probable cause, but I would want to know more and get it resolved. Ignoring low coolant warnings is a dangerous game and could cause massive problems if the coolant were to leak out completely.

If you're not planning on attempting this work yourself I would book it in to a mechanic soon and keep a close eye on your coolant level.

rex-x

It sounds more like head gasket failure, very common on that era of 1.9