I’m hoping for some help, I’m not a car person in no means!
I have V40 D2 65 plate, R line. Since about April, I have had an error message of coolant level low, I took it to Volvo, they did pressure test etc, couldn’t find any fault. But possible head gasket? I called them again because it didn’t go away. Booked in again, one month later.... established it was either Head Gasket or “cracked engine” but needed my car in for longer to strip the engine to be 100% for my third party warranty. Had it this week and it’s a new engine. They are saying the pistols are damaged some how, the metal jacket that protects them hasn’t! And even with a head gasket repaired it wouldn’t repair the seal and carry on damaging.
I want to know if any of you have any insight on How?? Can this just happen, have I done something as no one told me couldn’t drive it but I stopped on my own accord! I’m possibly in a position with a car broken and £12k of finance. I have raised a investigation to be conducted by my finance team, they are interested if it was default on the purchase of the car.
any help or insight as I am no car person, love driving but the mechanical nope, no idea!

 

If your car was consuming coolant, there's only a few places it can go - external to the engine you have hoses, the radiator, the heater core, the overflow reservoir and freeze plugs (which press into the engine block) which need to be checked for any staining/wetness. If its internal to the engine, it can be a seal - such as the head gasket which seals between the block and the head or as noted can be a crack in the head or the block. The thing about a failed head gasket is that it really depends where the failure is but generally its a two way street where anything high pressure will leak into areas of lower pressure. That means its possible for exhaust gasses (highest pressure) find there way into coolant and oil or the oil and coolant may leak into each other. So if any tests confirm oil/coolant mixing or HCs (unburnt fuel) is in the coolant, the head has to come off as a diagnostic. There's other tests as well but pretty much if the gasket is suspected, it needs to come off. Once the head is off, the shop should do a full inspect for flatness and if the gasket seems normal, next is to check for cracks in the head using a dye test (ie magnaflux). Big problem here is you'd already be about $1000 in on labor just to tell you you need another $1000 in parts if the head needs to be replaced. So to many the fast track is to simply find a used long block at a recycle yard (complete with block and head) and focus on doing the engine swap.

As to your issue with the pistons and cylinder walls - that's not the same issue as a head gasket repair. If the cylinder walls are damaged, you would have had compression issues and/or oil consumption prior to the head gasket failure - and the shop should have done a compression/leak down test as part of their head gasket diagnosis.

Again, shops can rehone cylinder walls but it may need new pistons/rings to return the engine to spec - which brings me back to the fast track point about replacing the engine with one from a recycle yard. Replacing new will likely cost in the $10K range (My VW CC had its long block replaced under warranty at 49K miles and the invoice read $9800 US paid by VW).