I have recently bought an A2 1.4 TDI SE from a private seller. The seller neglected to tell me that there was a problem with the car losing coolant at high speeds. I have taking it back 3 times to 2 different garages and neither can find any leaks. I have had the water pump & thermostat replaced and have so far spent £500, but the problem is still there. The engine has overheated twice. A 50 mile journey on the motorway and the coolant tank will be empty, however lots of short journeys around town and the loss is negligable. I am very worried that I am going to keep throwing money at this problem and not get it fixed, so am thinking of cutting my losses by attempting to get rid of this car (at a substantial loss I would imagine). Before I do this, would anyone have had experience of similar problems or have any suggestions as to what it might be?
Mystery coolant loss / overheating problem
- Thread starter markross
- Start date
Hi markross,
I'm sorry to hear your A2 ownership has got off to a bad start.
That's an awful lot of coolant to loose so any external leaks should be fairly obvious. It may help to temporarily remove the undertray so that coolant dripping from under the car after a run could easily seen.
On a previous car I had a radiator core leak which sprayed a fine mist out through the front grille when the engine got hot. The sweet smell of antifreeze was always evident but it took a long time to find where it was coming from.
Some garages have a special pump to pressurise the cooling system without running the car and this can make leak detection easier.
It's unlikely but the new water pump could be faulty
Other possibilities are a faulty head gasket or cracked galleries in the cyl head or block (I have never heard of this happening on an A2) This would normally show as water in the oil - check for emulsified oil on the dipstick and possibly oil level increases or (2) oil in the coolant - check for gunge in the header tank or an oily film floating on top of the coolant in the header tank
Dont be tempted to use Radweld or Barsleaks type additives in the coolant as most (if not all TDi's) have a Webasto auxiliary heater in the system and the sealant may damage the integral pump.
If you can provide a few more symptoms I may be able to make a better guess at the root cause of the problem
Cheers Spike
I'm sorry to hear your A2 ownership has got off to a bad start.
That's an awful lot of coolant to loose so any external leaks should be fairly obvious. It may help to temporarily remove the undertray so that coolant dripping from under the car after a run could easily seen.
On a previous car I had a radiator core leak which sprayed a fine mist out through the front grille when the engine got hot. The sweet smell of antifreeze was always evident but it took a long time to find where it was coming from.
Some garages have a special pump to pressurise the cooling system without running the car and this can make leak detection easier.
It's unlikely but the new water pump could be faulty
Other possibilities are a faulty head gasket or cracked galleries in the cyl head or block (I have never heard of this happening on an A2) This would normally show as water in the oil - check for emulsified oil on the dipstick and possibly oil level increases or (2) oil in the coolant - check for gunge in the header tank or an oily film floating on top of the coolant in the header tank
Dont be tempted to use Radweld or Barsleaks type additives in the coolant as most (if not all TDi's) have a Webasto auxiliary heater in the system and the sealant may damage the integral pump.
If you can provide a few more symptoms I may be able to make a better guess at the root cause of the problem
Cheers Spike
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Thanks for your reply Spike. The last 2 times I have taken it to an Audi specialist and he pressure tested it and could find no leaks. He spoke to the Audi garage to find out if they had heard of anything similar, and they informed him that they had had an A2 in recently with exactly the same symptoms as mine. They spent a week with the car trying to discover what the problem was and it turned out to be a warped cylinder head. So if it's this I have been told the engine will need to be stripped down and if the cylinder head can be repaired it will cost around £300, but if not it will need to be replaced at a cost of around £1400!
The guy who sold me the car obviously knew there was a problem with it, and I am now wondering if I have any legal comeback. I'm guessing not as it was a private sale, but I am now in a bad situation as I can't really afford £1400 to repair it, and I'm not going to be able to sell the car except for a lot less than what I paid for it.
The guy who sold me the car obviously knew there was a problem with it, and I am now wondering if I have any legal comeback. I'm guessing not as it was a private sale, but I am now in a bad situation as I can't really afford £1400 to repair it, and I'm not going to be able to sell the car except for a lot less than what I paid for it.
Hi markross
If you have motor insurance with legal cover, call the help line to get advice on your rights regarding any comeback on a private sale.
I think Audi supply different thickness head gaskets to allow for skimming so it's unlikely you will need a new head - but if you'r unlucky, check this e.bay advert out - I've done a quick comparison on the A2 and Polo cyl heads and they appear identical
http://cgi.ebay.co.uk/VW-POLO-1-4-T...4647476711QQcategoryZ9889QQrdZ1QQcmdZViewItem
Cheers Spike
If you have motor insurance with legal cover, call the help line to get advice on your rights regarding any comeback on a private sale.
I think Audi supply different thickness head gaskets to allow for skimming so it's unlikely you will need a new head - but if you'r unlucky, check this e.bay advert out - I've done a quick comparison on the A2 and Polo cyl heads and they appear identical
http://cgi.ebay.co.uk/VW-POLO-1-4-T...4647476711QQcategoryZ9889QQrdZ1QQcmdZViewItem
Cheers Spike
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Hi markross
I just checked the manual and according to Audi, the cyl head cannot be skimmed. The head flatness tolerance is 0.1mm - checked with a straight edge and feeler gauges. Different thickness head gaskets are used to compensate for variations in piston protrusion due to production tolerances. The procedure is to check the markings on the existing head gasket and replace it with one of the same thickness. They also recommend the head bolts are replaced at the same time and the engine is filled with new coolant.
Cheers Spike
I just checked the manual and according to Audi, the cyl head cannot be skimmed. The head flatness tolerance is 0.1mm - checked with a straight edge and feeler gauges. Different thickness head gaskets are used to compensate for variations in piston protrusion due to production tolerances. The procedure is to check the markings on the existing head gasket and replace it with one of the same thickness. They also recommend the head bolts are replaced at the same time and the engine is filled with new coolant.
Cheers Spike
Cheers for the info Spike. The car still isn't fixed, as I can't afford it at the moment. However, I have been running some tests on the car to see if I can work out where the coolant loss is and when it happens. I made 2 similar motorway journeys, both approximately 60 miles. The first I drove at about 50-60mph all the way. When I arrived back I checked the coolant and there was no noticeable loss. The same journey again at 70-90mph and after about 30 miles the coolant warning alert came on. On checking the coolant level was right at the bottom of the tank. In total on the journey I lost nearly 2 litres of water.
I think I have also worked out where the coolant loss is occurring. It seems to be bubbling out through the valve at the top of the water tank (where the coolant is topped up), as I could see coolant in this valve and round the rim of the tank and also below the tank a little pool of water had accumulated. Does this sound like it could be caused by a faulty cylinder or something else?
Many thanks for your help.
Mark
I think I have also worked out where the coolant loss is occurring. It seems to be bubbling out through the valve at the top of the water tank (where the coolant is topped up), as I could see coolant in this valve and round the rim of the tank and also below the tank a little pool of water had accumulated. Does this sound like it could be caused by a faulty cylinder or something else?
Many thanks for your help.
Mark
spike said:
Hi Mark
It does unfortunatly sound like the early stages of headgasket problems. At high engine loads the gasket is not sealing properly, allowing combustion gas to escape into the cooling galleries and pressurise the system. The pressure cap on the header tank is rated at 15psi (I think) so once this pressure is exceeded, coolant escapes through the valve in the cap
The quicker you get it checked the more chance you have af getting away with just replacing the headgasket and possibly flatting the head off on a piece of plate glass with coarse 'wet and dry' sandpaper stuck on. You won't need a full skim and a thicker headgasket if the surface will clean up by removing the odd thou (.025mm for metric folk)
Cheers Spike
It does unfortunatly sound like the early stages of headgasket problems. At high engine loads the gasket is not sealing properly, allowing combustion gas to escape into the cooling galleries and pressurise the system. The pressure cap on the header tank is rated at 15psi (I think) so once this pressure is exceeded, coolant escapes through the valve in the cap
The quicker you get it checked the more chance you have af getting away with just replacing the headgasket and possibly flatting the head off on a piece of plate glass with coarse 'wet and dry' sandpaper stuck on. You won't need a full skim and a thicker headgasket if the surface will clean up by removing the odd thou (.025mm for metric folk)
Cheers Spike
The saga continues....
Finally got a new cylinder head fitted a couple of weeks ago. The car seemed fine (at last!). However yesterday evening it failed to start! It was turned over ok, but just not firing up. Sent it back to the garage who replaced the cylinder and they say it's the cambelt! It hasn't broken but they'd mentioned someone about it slipping "quite a few teeth".
Could this have been caused when they put the engine back together after fitting the new cylinder head? I find it a slight coincidence that this has happened a couple of weeks after the work was done. Should I be looking a getting some money off the cambelt work?
I'm beginning to think my car is cursed...
Finally got a new cylinder head fitted a couple of weeks ago. The car seemed fine (at last!). However yesterday evening it failed to start! It was turned over ok, but just not firing up. Sent it back to the garage who replaced the cylinder and they say it's the cambelt! It hasn't broken but they'd mentioned someone about it slipping "quite a few teeth".
Could this have been caused when they put the engine back together after fitting the new cylinder head? I find it a slight coincidence that this has happened a couple of weeks after the work was done. Should I be looking a getting some money off the cambelt work?
I'm beginning to think my car is cursed...
Hi, thanks for the update
I think the devil is on your side at the moment - you'r extremely lucky to get away with slipped timing. This could have so easily wrecked your new cyl head, a piston or two and possibly the turbo if debris had gone down the exhaust ports.
It sounds very much like the garage either did not set the cambelt tension correctly or forgot to fully tighten something. To fix it, a new cambelt is a must, even if the current one only did a few miles. Also check the idler pulleys and replace them if there are any signs of damage or they are approaching their service life (now 4 years or 60,000 miles)
Cheers Spike
I think the devil is on your side at the moment - you'r extremely lucky to get away with slipped timing. This could have so easily wrecked your new cyl head, a piston or two and possibly the turbo if debris had gone down the exhaust ports.
It sounds very much like the garage either did not set the cambelt tension correctly or forgot to fully tighten something. To fix it, a new cambelt is a must, even if the current one only did a few miles. Also check the idler pulleys and replace them if there are any signs of damage or they are approaching their service life (now 4 years or 60,000 miles)
Cheers Spike
abefromann
Member
Ditto
Hi Mark,
Glad to hear you got that sorted - especially seeing as i have an identical problem.
Just going through the usual diagnostics with my second garage - was about to tackle the water pump next but will get the garage to change the cylinder head instead.
Would it make sense to do the cambelt at the same time? im currently at 52k so it'll need doing soon.
How much did it cost you?
Rgds
Adam
Hi Mark,
Glad to hear you got that sorted - especially seeing as i have an identical problem.
Just going through the usual diagnostics with my second garage - was about to tackle the water pump next but will get the garage to change the cylinder head instead.
Would it make sense to do the cambelt at the same time? im currently at 52k so it'll need doing soon.
How much did it cost you?
Rgds
Adam
