For quite some time now when starting the engine hot or cold there is an engine "knock" or "ping" sound happening just once at the first stroke of the engine, it's loud enough to also sound like a motor mount has gone south, car has exhibited this nasty habit now since I owned the car and as it now is more often than sporadically am getting concerned to the point of wanting to know what it is and how to fix/eliminate it or is this something all 545's sound like sometime?
Used to get the occasional misfire code from cyl. #4 and have since replaced that spark plug some time ago, no more misfire codes but the "clunk" when starting engine still occurs.

Would like some feedback from other past and present 545 drivers, if this is a "feature" or do I have something else to fix?

Would love to hear any suggestions..

 

Hi cmyachtie,


Unfortunately, I don't have any suggestions. But I do have the same loud knock at start-up as you describe, i.e. almost like a bad motor or trans mount. I would be very interested in what you find out.


For now I have to deal with my water pump which went from having a tiny bit of play last weekend to fully letting go on the ride home yesterday!! Very embarrassing riding through my little home town in the flatbed with my car on back! :-( I've had the car for almost a year now and this is the first real problem.

 

Thanks for your reply,

Must be a Canadian thingy heh....LOL

Have posted this on two of the most heavyly attended forums and NADA response on this knocking, strange I must say, I always figured it was normal but thought I'd shout out here and there but we must be the only ones....
Good luck with you waterpump situation!

Never could figure why BMW seems unable to have decent waterpumps on their cars....

 

OK replaced all 8 sparkplugs and after starting it today about 6 times during my trip still,got the crazy knocking once so eliminate the plugs as the cause.

 

Call me stupid .......but have figured out what this knocking noise is when starting it's the steering wheel moving down(Comfort Access) I guess. I drive with my wheel all the way down and When I get in the car it is in the upper default position, after turning the ignition on the second (starting position), it moves down and that provides me wth that noise, kind of a "doh" moment for me....
Anyone else experience this?

 

Is it a rumble squeaky , creaky type sound as the wheel goes down ? Sorta like an old creaky door ?

 

No squeak, just this "clunking" sound, easily confused with a misfire......
When Iget a chance am gonna try to fit myself in the footwell and have a look down there, just not one of those "gotta fix it right away" .
Maybe should post a video to get the sound here.

 

Mine has been doing the same thing for quite a while now. It sounds like the whole steering column needs a good lube job.