charlieaf92
Member
Hello all
I have what I believe is a bad pulley but could use some input and experience before I start taking things apart. Here is a short description of the problem.
I first noticed it about one year ago immediately after having my Z4 (3.0i) serviced by BMW. It sounded kind of like a supercharger whine. It happened to be a very cold day. Once the car warmed up it was gone. It didn't happen much but after and seemed like it only happened on very cold days. Drove the car all winter and this summer with no real issues.
Now, the weather is getting cold again and the whine is back. Its worst when it is cold outside and the car has not warmed up. It is getting progressively louder and worse. It seems like it happens most in the 1900-2100 RPM range.
I've gone over the intake pipes with my hands and visually inspected them while on the car looking for splits or leaks, but haven't found anything. With the hood up, the sound seems to be coming from the front of the engine (pulley/belt area) but it is very hard to tell.
Just purchased an automotive stethoscope but I can only really check the alternator and the idle pulley that is directly next to it. There seems to be considerably more noise on the pulley vs. alternator which makes me think that is the problem.
Has anyone experienced something similar? Any advice would be appreciated. My next step at this point is to loosen the belt and turn the pulley by hand to see if it feels worn out.
Thanks!
Charlie
I have what I believe is a bad pulley but could use some input and experience before I start taking things apart. Here is a short description of the problem.
I first noticed it about one year ago immediately after having my Z4 (3.0i) serviced by BMW. It sounded kind of like a supercharger whine. It happened to be a very cold day. Once the car warmed up it was gone. It didn't happen much but after and seemed like it only happened on very cold days. Drove the car all winter and this summer with no real issues.
Now, the weather is getting cold again and the whine is back. Its worst when it is cold outside and the car has not warmed up. It is getting progressively louder and worse. It seems like it happens most in the 1900-2100 RPM range.
I've gone over the intake pipes with my hands and visually inspected them while on the car looking for splits or leaks, but haven't found anything. With the hood up, the sound seems to be coming from the front of the engine (pulley/belt area) but it is very hard to tell.
Just purchased an automotive stethoscope but I can only really check the alternator and the idle pulley that is directly next to it. There seems to be considerably more noise on the pulley vs. alternator which makes me think that is the problem.
Has anyone experienced something similar? Any advice would be appreciated. My next step at this point is to loosen the belt and turn the pulley by hand to see if it feels worn out.
Thanks!
Charlie