coolant problem!!!help!!!!

[t44ka_g]

Hi all!!!!!!!!!!!!

I am a owner of a mk4 gt tdi 115bhp golf!!!!! i have had it for a month and had it in the vw garage at least 7 times for the same problem.   The coolant light beeps as i drive signaling a warning to stop.  i check the the expansion tank and sometimes the water is fine and sometimes not.  there is no visability of anywater being lost on the floor as i am parked.  i have changed thermosat and they have checked waterpump and head gasket is ok!!!!!!!!

as i am driving sometims the light coms on and sometimes go off after 30 secs but sometimes stays on for longer!!!!!!! VW havent a clue at the moment!!!!!

someone please please help!!!!!!!!!

anyone got any ideas or any advice please mail me on t44ka_g@yahoo.co.uk.

thanks

[golfvr6]

Do the mk4 have the same sort of expansion tank as mk3s? could be a faulty sensor on the expansion tank making the light flash.

[modulater]

I would imagine that the expansion tank has a float sender, Try and find it and disconnect it and see what happens. Also what do you mean by the water is sometimes fine, other times not?

[t44ka_g]

thanks for the replys!!!!!

i dont think it is a faulty switch because i had that changed.  but the floater idea could work but what i am worried about is for definatley i know i am losing water because i have to keep on topping it up nearly every day.  but i dont know how i am losing it??? it is really confusing and i am getting fed up of the problem!!!!

if anyone else has any ideas please keep me posted thanks!!!!!!!

[golfvr6]

Its either leaking externally or into the engine.

[DieselMonkey]

You say some times its OK and sometimes its not....... so if you are topping it up everyday is it just ok once topped up or is it still ok after a substantial amount of driving ?

Your VW dealer isnt stupid, they would have checked all the usual things. If it is leaking internally into the engine, the oil would have turned a sludge type grey after a few hours driving or if it wasnt that much water then there would only be a certain amount of sludge formed on top of the rocker cover, or quicker way to check is to simply look at the bottom of the oil filler cap. The only true way to tell if it is leaking internally is, after it has sat overnight and is cold, remove the sump plug... ANY water that is in the sump will come out crystal clear straight away as water goes to the bottom of oil. If you check this yourself, be sure to put the plug in straight away to save yourself any topping up. You'll probably only need a 19mm ring spanner for this, unless they have changed it from the mk III.

But if it isnt this..... and there isnt any damp patches on the ground where the car sits then the coolant lost may be caught somewhere in the vehicle. In this case the cars heating system could be suspected. Its the only place where coolant might be able to escape yet not actually show up unless large amounts where lost. Are the mats and floor in the front slightly damp at any time ?

How much water is usually required to bring back up to the max level ? Remember to buy some VW antifreeze / coolant to keep the systems concentration the same for corrosion protection.

As i previously said, the quickest way to see if coolant is leaving the cooling system and entering the crankcase is to remove the sump plug carefully, hold it in as you remove it and just as it is off the last thread tilt it to the side for 1 second and see if there is any coolant present. If there is it will be the first thing to leave.

If there is coolant then there could be many things. Probably not a head gasket problem, probably more like oil cooler, liner seals or a pitted liner, but this is very unlikely given the age of the engine and quality of coolant today.

Let us know what you find from the sump plug. Hope this helps