Coolant

[MoonlightBlueVR6 0]

Hi

 

Really sorry to ask such a silly question but I have no manual with my VR6 and am not that clued up about such things...quite new to all this only having owned the car a month...

 

The coolant warning light has started flashing on the dash of my 92k VR6 and on checking under the bonnet I noticed the pink stuff was well under minimum. What should I be topping it up with - tap water? something from Halfords or something from VW only.

 

I have also noticed a small leak on the driveway - I'm assuming a possible relationship here - what's the best way to try to isolate a leak?

 

I do have a slight low rev misfire too (circa 2000 revs), but everything sounds fine on tickover and there is plenty of smooth power as you climb the rev range.

 

Anything to worry about do you think?

 

Thanks and apologies again!! Any help much appreciated!!

 

Paul

[dr_mat 0]

ISTR that all VR6s have a slight misfire if you hold the engine revs to ~2000.. So don't worry too much about that. (Even Vince at Stealth commented on that one once.)

 

Coolant leaks are most likely to be caused by (in order, pretty much!)

 

- heater matrix supply pipe on rear of cylinder head (hard to see - and usually caused by sloppy engine mounts)

- auxiliary coolant pump (right rear of the engine as you look under the bonnet)

- radiator

- main water pump (lower left of the engine, driven by the alternator belt)

 

But general loss of water can in ultimately mean anything from head gasket to just the expansion tank pressure cap being faulty ..!

 

As for topping up, think you're supposed to use distilled water or proper coolant. GSF sell the pink G12+ VW coolant (made by Febi) for cheap money, so get some of that.

[Jim 2]

I normally use boiled kettle water for top ups and obviously as the good doctor says, only ever use VW G12+ - you'll know its the right stuff as its a lovely flourescent pink colour :)

[lottysvdub 0]

this may sound like a stupid question but why do you have to use VW G12+ , ive havent used it could this be possible a reason why my car seems to run hotter than i like ? and possible causing poor idle problems if the sensors arnt working correctly? :confused4:

[craigowl 0]

I think G12+ may cause problems if it is mixed with other coolants.

G12 + forms a gel even when mixed with some older type of VW coolant - it has to be used unadulterated, I believe.

Possibly the best thing to do is to have your cooling system flushed and refilled with 50% G12+ and 50% pure water.

 

At least by coming on to this forum you will find answers to most common problems without having to root around too much. Good Luck.

[lottysvdub 0]

nice one mate i will try that next weekend when ive got time , its got to be worth giving a go ive tryed new sensors and alsorts of other things but ive not heard of this before , again cheers buddy :D

[MoonlightBlueVR6 0]

Thank you particularly Dr Mat and Jim for your helpful replies. I'll get her topped up tonight with kettle water and order some of the special coolant tomorrow first thing - then when I next have some daylight and a spare 10 mins I'll go around the engine bay with a microsope focussing on the areas you suggest Dr Mat.

 

One more question.... am I best to have the engine running / have just come back from a decent run if I'm to have the best chance of isolating a leak?

 

Thanks again

 

Paul

[Jim 2]

Yeah - just leave the engine on, open the bonnet and start poking around with a torch!

[MoonlightBlueVR6 0]

Cheers Jim

[Supercharged 2]

Lets clear this up, The FEBI stuff is the older G12 not G12+ which is a superceded part with better anti-corrosion properties,

 

G12+ can be mixed with G11 or G12 fine without any 'gel' effects...

 

(do not mix G12 and G11 tho and G11 is what all Corrado's came with AFAIK so it's very important you get the G12+ and not the older stuff, even if the coolant is currently pink it may not have been flushed totally when last changed)

 

The other classic place for a leak on a VR is the thermostat houding underneath the aux pump, look for white deposits...

 

For now i'd just top up with mineral water until you find the source of the leak, get your self 2 botles of G12+ and a new (blue) expansion tank cap and change the coolant before winter.

 

2 bottles = 3 litres = 33% (30% in an auto) which gives the best compromise between cooling and antifreeze for the UK climate.

[MoonlightBlueVR6 0]

Thanks Supercharged - but why would I need a new cap?

Apologies if I'm being dumb.

 

Cheers

 

Paul

[catch_twotwo 0]

The seal on the older caps can go... this causes a pressure inbalance which can cause problems.

[Supercharged 2]

MoonlightBlueVR6, they have also superceded the cap with a new sort and made them blue rather than black for easy identification, if yours is black the the pressure relief valve maybe playing up (or will do at some point) so best to get a new one - less than a fiver from VW

[catch_twotwo 0]

Do you have a part number fo easy ordering.... I need to get some parts in so might as well replace mine as well.

[Supercharged 2]

It's a bin part mate (ie they keep them on the shelf)

[catch_twotwo 0]

It's a bin part mate (ie they keep them on the shelf)

 

Try explaining that in German :lol:

 

Ich möchte ein thingy cap.... im blau bitte :oops:

 

I'll reinstall my ETKA if I can find it..... must be somewhere

[Supercharged 2]

Hehe - I'll look on ETKA when I get home...

[Supercharged 2]

1H0 121 321 C

[latestarter2 0]

is this stuff (g12+) available from VW ?

[craigowl 0]

latestarter2 wrote

 

is this stuff (g12+) available from VW ?

 

Yes - it is VAG's own stuff. Reasonable price, too.

[Trig 0]

Yup, you'll need 2 bottles to fill a VR from empty.

[Jim Bowen 1]

reading my manual is says never to use water, always use the proper coolant at no less than 40% mix.

[craigowl 0]

Supercharged wrote

1H0 121 321 C

 

Thanks for good info about coolant and new blue reservoir cap, Supercharged. 8)

Nowt wrong with my 11-year old black original but have just ordered new one from local VAG dealer. £5.73 with CCGB discount.

(1st purchase at Advantage VW, Stirling - well done to them for granting 10% discount on asking.)

[Trig 0]

reading my manual is says never to use water, always use the proper coolant at no less than 40% mix.

 

So that means 60% water then... :)

[Supercharged 2]

reading my manual is says never to use water, always use the proper coolant at no less than 40% mix.

 

So that means 60% water then... :)

 

No ice please...