another noise problem !! [Archive] - Bimmerfest - BMW Forums

: another noise problem !!

11-08-2008, 09:36 PM
i know this has got to be like the 10,000th noise post but i can't find any existing thread that matches my problem.

symptoms: chirpy like noise from engine sounds alot like a bad belt. but - belts have been replaced, and a few weeks ago when i replaced a leaking radiator i also did the water pump, fan clutch, all the tension and deflection pullies. even using a stethoscope, i can't seem to isolate the problem. i'm think possibly timing chain tensioners, but it doesn't sound like the one's i've heard on youtube.

also unique:

1 - it does not do it at start up and with a cold engine - only when the engine is warm - and,

2 - it only makes the noise at idle. if the engine is rev'ed just a little it disappears

any idea's??? i guess i could record it and youtube it, but was hoping someone here has already solved this mystery!

bimmer dot info
11-10-2008, 09:49 AM
Bad bearing on the alternator?

attack eagle
11-10-2008, 11:45 AM
yep, that'd be my next guess too.

11-13-2008, 06:22 AM
It sound like you need to reset your valve ajustment

11-17-2008, 10:09 AM
it's definitly not the alternator bearings, i think that would really stand out with the stethoscope. will do a valve adjustment this week. i had never even thought about that! thanks!!!

11-30-2008, 06:13 AM
sat down to order some parts and it kinda dawned on me, doesn't an m50 engine have hydraulic lifters? how can you do a valve adjustment?

i am thinking i'll record a youtube video and post it - might make it easier to help me determine what going on.

bimmer dot info
12-01-2008, 08:53 AM
The M50 has hydraulic lifters. There is no adjustment.

12-03-2008, 08:18 AM

More than likely......catch your breath...Power sterring pump.

how do I know?

just replaced mine.... chirpy annoying sound GONE.

but......rrrrrrrrrrrrrrrrrrr the dough, the dough!!!!

get the OEM one!! Its worth it!!

hope it helps!!!!


12-03-2008, 08:19 AM

meant to spell "steering"



12-03-2008, 09:31 AM
One other possibility is your belts. Not sure how familiar you are with them or if done by a mechanic... Some times they do not do it either. When a new belt is put in place there is a slight stretch factor. The car should be run for 10 minutes and then retention the new belts. If this is not done, sometimes, not always, your new belts will squeak.

A good and cheap way to tell if it is a belt is to get an inexpensive can of belt dressing and spray on the underside of each belt on at a time wile the car is running. If you hear the noise stop, re-tension that belt.

Just another avenue to troubleshoot before you buy a new Power Steering pump.