Hello, my 2003 Golf Mk4 2L broke down with temp gauge on half as it usually is and I'm always checking it but the STOP alert with red arrows came on the dash; temp gauge was redlining. So I braked and pulled over with no loss of power/smoke/noise/lurching. Had car towed to nearest mechanic as I'm 600kms from home and ordered the part and 7 litres of pre-mix G12 coolant. Checked the oil and it wasn't milky. Car idled nicely for the roadside assistance guy and for the second towtruck driver taking it to the mechanic who drove it onto the truck. I thought the mechanic would replace the hose connector then flush and bleed the cooling system and let the car run to check the temperature. I told the service manager I was worried it might be something more serious and not to drive it at any cost before checking things but when I got there today they were driving it back into the yard for the SECOND TIME. I asked the guy driving it if he'd already put the coolant in and he said nahh we topped it up and I said what with?? They said water, and I said did you bleed it and he said it was bled already, and I said what are you talking about?? He then told me it's running badly and said they'd topped it up with 3L of water then took it for two spins. Unbelievable. And now when you start it up the fan cuts in after about 10 seconds and it sounds like its struggling a bit with the idling. Not a good sign and I'm thinking it could be a cylinder head gasket but the fact that there was still half the water in the system and no milky oil and no power loss or other sign, I was really hanging on to this thing called optimism. And it really looked to me like this hose was pitted and had sheared off and that this was the cause of the overheating through loss of water and pressure. Anyway, I asked this muppet of a mechanic what he was planning to do next and if he had checked the spark plugs to see if it could be the head and I asked if he had the gear to do a compression test and he said yes and he'd do the compression test in the moring, so that's the next step. He didn't even check the thermostat. I'm so nervous and worried and I have no confidence in this guy who's apparently been a mechanic for 30 years. He said he "bled" the cooling system by leaving the cap off the reservoir and driving it or letting it run as he reckons when his car overheats, he just drives it around the block and I said yeah but your system is CLOSED and mine burst open and is full of AIR. Sorry for rambling but I am freaking out. I know I stopped it as soon as the temp gauge was up and I don't know if this split hose was the cause or a symptom of a bigger problem i.e. the cylinder head gasket going but if it was just the hose could there be a good chance that my engine was fine before they drove it?? I wonder if you have some experience and could suggest what we should look at and what steps should be taken next in which order, and finally, if driving it could have done any further damage. Thanks so much. I've been staying in a motel for five days while awaiting the part and coolant but I'll likely have to put us both on a truck and head back to Melbourne to a Volkswagen specialist.