[Bshely26]

Okay so I have a 2010 335i with the JB4 installed. The problem I am having is when I go to start the car and press the push button it takes a couple times to start. It clicks like it's going to start, but it does not. Yet sometimes it starts right up. One thing I noticed is if it's hooked up to a battery charger it has started right up on the first push each time. So I thought it was the battery. It checked out though, but I still had it replaced under warranty. Well it did it again, but this time only after two button pushes it started. It seems to depend on how long I leave it parked. Yet after replacing the battery it usually only takes 2-3 times and it starts. So I took it to the dealership and had the battery registered and to check the problem. They said it was because the JB4 or "aftermarket tune" was causing a issue with the k-can line. Has anyone heard of this issue before being caused by the JB4. Thanks for any help!

[Randomaccess335]

Mine did that for while, turned out to be the starter.
After it stopped working at all I replaced the starter now it starts up properly first push every time.

[Velocity26]

Same as random ... that is the usually the first sign of a failing starter. Mine laster 40,000 miles and then did the exact same thing. When it does not start, get a piece of PVC pipe, or stick. and press it against the starter and hit it with a small hammer. It will jar the starter enough to move the internals slightly and it will start right up. Unfortunately, it will get progressively worse. If it was less difficult to remove and replace I might recommend that you remove the starter and clean where the brushes contact the stator and that could fix it for a while. Your only other alternative is to replace it and move on.