Mini Cooper Burning Coolant

2007 Mini Cooper (Not the S model) burning coolant. Have brought to two mechanics and no visible external leaks. Both did a pressure test and was fine. They think the head gasket is blown. Car is operating normal.

Any idea what it could be or am I facing a large repair bill?

I don’t think a pressure test can pass if the head gasket is blown. I think you need a third mechanic. I do agree with them though that a blown head gasket is more than likely your problem.

I agree that a breached head gasket is likely to be the source of the problem, and that you need a mechanic who will do more than a mere pressure test.

As to the cost, I have to say that I don’t know how accessible everything is under the hood of a Mini, but I suspect that the very close quarters will make the job more difficult/expensive. On some small cars where everything is crammed-in very tightly, it can necessitate removing accessories like…A/C compressor…alternator…various hoses…in order to actually do the job.

I think you should be prepared for a bill in the area of perhaps $600-700, and if it turns out to be less, then you will be happier than if you were not prepared for a large bill.

VDCDriver I think an estimate of $600-$700 would be on the low side. A friend of my wife had a Saturn 1 with the same problem and it cost $900. Everything on a Mini is more expensive, so I would budget about $1000 for a head gasket repair.

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You may well be correct, Doc!

When the head gaskets (two) needed to be replaced on my '97 Outback (which had clocked ~130k miles and was long out of warranty), the dealership charged me ~$400 for the job. They said that they were giving me a good break on the price, and now I suppose that it really was a good break.

Sad to say, the family that had owned the dealership for over 25 years recently sold it, and I doubt if I will be treated as well by the new owners, who own at least one other dealership. Already the very reasonable service prices have gone up, and I doubt that they will be extending good will to the same extent as the family who previously owned the place.

Thanks for the input. The car, unfortunately has only 70k on it. Could the car pass the pressure test if the head gasket is only leaking slightly? I am going to check also, but will the exhaust color/smell indicate a leak?

FYI, repairpal.com gives an estimate of $2100 to $2900 for your head gasket replacement, based on labor rates where I live (near Boston).

“The car, unfortunately has only 70k on it”

repairpal.com gives an estimate of $2100 to $2900 for your head gasket replacement”

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Yikes!

In retrospect, I guess it does make sense that Consumer Reports recently rated Mini as the most problem-prone, least-reliable brand.

A head gasket can leak in one or more ways.
External leak not affecting performance and can be visually seen.
Internal leak not affecting performance and mixing with engine oil.
Breach into a combustion chamber which will cause a performance issue and white smoke out of the tailpipe.

You might clarify the “burning coolant” comment as that could be interpreted as a combustion chamber breach and is not the same thing as “coolant loss”.

If the only thing the shop did before pronouncing a blown head gasket is to run a cooling system pressure test then I would not plow headlong into a head gasket repair at this point without covering a few more bases; compression test, hydrocarbon test, vacuum test, etc.

Coolant loss could be caused by something like a weak pressure cap.

thanks everyone for your input. I’ve had two mechanics run pressures test and have come up empty handed. The second mechanic noted (1) he had to top up the coolant - so it’s still leaking somewhere (2) did not appear to be in the oil (3) thermostat housing was fine (4) the mini was not showing any signs that to date that a head gasket may blow. However, he recommended I consider trading in the car BEFORE it starts to show signs. ok4450 - The compression, hydrocarbon test and vacuum test you mentioned - do you know how much thoses kind of tests typically run? I’m debating if I just trade the car in and be done with it, or put a few more dollars in for a few more tests.

If you’re a DIY type, you can buy a hydrocarbon test kit and do it yourself:

I agree with the post by @VDCdriver above, expect the head gasket replacement bill to be well above $1000. On this car, if less than $2000 I’d be surprised.

If you think about it, it’s odd that a head gasket could cost so much, after all it is just a gasket. A weird shaped piece of paper is all it is. How much could a gasket cost? But of course the cost is the labor involved. At $100/hour, it adds up quickly. Removing the cylinder head may involve both the intake and exhaust manifolds too, and the fuel injection system components, and removal of other stuff to provide the needed clearance. Plus they may recommend to replace stuff not broken, simply b/c everything is already taken apart at the time.

Has the engine ever severely overheated? If so, other parts of the engine might be damaged or have warped and need resurfacing. Fixing those may add to the cost.