QuestionCar has been overheating. Apparently radiator part broke off at the hose - replaced radiator. Mechanic says its plastic and melts.
Runs fine for three weeks. then I see the needle dart up to red but it comes back down quickly. This happens twoice one week - then it goes to red ans stays there. All times I have immediately pulled over - I have not driven far on a full red.
Water pump replaced. It;s plastic the mechanics said.
Runs rough - check engine light comes on - go back by and they say my oil and gas caps are loose. Light goes off. Next day it goes red again but after stopping it comes back to normal and I'm able to drive it to the mechanic. Now they say it's a blown head gasket and it's $2000 IF the head is not cracked.
Does this make sense? Why are things in a engine plastic? Is it possible the head is cracked even though I have had the car towed to and fro? Would I be better off at a dealer?
AnswerI don't know where your mechanic gets his parts, but the OEM waterpump for this car is NOT plastic and most likely caused your head gasket to go. The radiator is made of a composite similar to plastic for better heat transfir. The fact that the radiator and pump needed to be replaced and the needle "jumps" up tells me your car is overheating and the "idiot gauge" on the dash is bad. At no point under any cercumstances should the temp gauge jump, if that is occuring you know you have a spike in the line voltage (caused by frayed wires or a bad sensor/ sensor ground). The engine in fact was extreamely hot the entire time you were driveing it, the gauge was lieing.
It is quite possible that the head gasket has blown, these engines cannot take extreame temperatures (extreame driveing and mileage....no problem). the cast block and the aluminum have different expansion rates and since they are bolted together they warp, so even if the head isn't cracked, it will need to be redecked, i don't recomend tou go back to that mechanic again, if he couldn't catch a bad gauge and buys cheap parts that have critical functions to the engines life and performance. The only good aftermarket pumps do is help pay for my boat out back since they overheat so many engines. water pump, timing belt/chains and many bolts should always be bought from the manufacture (BMW dealership)
You have mechanics that are trying to take the rich snob BMW owners money; since you drive a BMW you must be rich....right?!
I'm sick of mechanics takeing advantage of BMW owners because they think we're all suckers with cash.
-cheers
