Audi Repair Questions? Ask a Mechanic for Answers ASAP
Hello, and thank you for allowing me the opportunity to help you. If I am not online when you are, please allow me time to return. If there are not any noticeable exterior leaks then you may have an internal engine problem. I would have the cooling system pressure tested to see if there are any leaks. If there is nothing shown during the pressure test you need to do a compression test. This will let you know what is wrong with that cylinder. Also see if there is coolant on the compression tester during the test. There may be coolant leaking into that cylinder as the vehicle sits which would explain the coolant loss and the running and misfire. If the coolant was that bad then you may have a head gasket problem. Do you plan on doing this work yourself?
I've been doing all the work since the coolant problem had been "fixed". Compression test were done and it's holding good compression. There isn't any water in the oil or oil in the coolant. i changed the oil after the coolant was done also. Full synthetic in it. Like I said, there isn't a miss except on start up and it doesn't always happen then either. But other than that there's not an obvious misfire. Which is why I think it has to be more simple than a head gasket. Question, the fuel rail line was lying on the head, and burned through the rubber that protects the wires, the wires weren't frayed or burnt, but exposed, so i put electrical tape on it. Could that cause that cylinder misfire?
How exactly do you go about going through a carbon cleaning. I wouldn't necessarily say i'm confident that it's not the head gasket, but I feel if that was the case, there would be some other indicators that point to that direction and I'm not noticing any. Like bad oil, or smoking, driving rough. I'm just fed up. I plan on doing the coolant test though.