Out Of Options:(

[e34it]

Well gentleman/ladies, the sound in the M5 still hasnt been found, the engine was run without the tranny, and the sound is still there, my mechanic says he hears it coming from the ABS brake controller system in the engine comp, and it vibrates to the rear of the car, supposedly he thinks that is the source, sounds like ******** to me. I personally think the sound is coming from the motor somewhere, I'm asking for my car back today, i have three options, sell it and get what i can out of it, keep it and live with it and drive it until this sound/vibration destroys it, or go to the BMW dealer and let them have a crack at it, what would you all recommend? I really want to keep it, but i know i won't enjoy it with this problem, please give suggestions. Thanks!

[Kalevera]

Is it a knock? maybe the motor needs a rebuild -- happens on the S38B36/38. I guess if it was a knock, it wouldn't vibrate throughout the car, but who knows. best, whit

[e34it]

Its more of a grind or a whirring, metal noise that stays constant with RPMs, when off the throttle the noise is gone,

[Interceptor]

Its more of a grind or a whirring, metal noise that stays constant with RPMs, when off the throttle the noise is gone,

You should take your car to someone who is familiar with bimmers and let him upen up the engine.

[emw525E34]

Interceptor,

I see you are using Denso Irudium plugsin your M50 motor. Can you advise how you like it and what part numbers these plugs are ?. I wanted options from Bosch, about to try NGK but Denso seems a higher brand in the Jap supplier chain.
Thx.

[Interceptor]

Interceptor,

I see you are using Denso Irudium plugsin your M50 motor. Can you advise how you like it and what part numbers these plugs are ?. I wanted options from Bosch, about to try NGK but Denso seems a higher brand in the Jap supplier chain.
Thx.

Denso is THE ultimate spark plug manufacturer in the world, not only in Japan. I like 'em very much - smoother idle and revving, a bit more high-end power and slightly lower fuel consumption. I don't know the exact P/N because I'm at work currently, but I'll post it once I get back home. But I must warn you - they're very expensive here, around $25 a piece! And you need six of them! Btw., I have non-VANOS M50.

[632 Regal]

did you remove the front belts to eliminate the power steering pump and pully noises? The steering pump is a simple hydraulic pump and if its bad will cause the sound that you described. SImple enough to do too.

[632 Regal]

and then look into the oil pump? A bad low end or bearings wont make a whirr sound.

[Paul in NZ]

i think you have answere your own question

or go to the BMW dealer and let them have a crack at it,

I really want to keep it, but i know i won't enjoy it with this problem,

ask them just to look at it thought not to actually fix it.once they have given teir opinion go from there,but see if you can eliminate all the accessories first,ie water pump,alternator,ps pump,etc etcif you use a long scewdiriver as a stethescopee(hold the handle near your ear,you may be able to listen while you manipulate the throttle with your hand,be easier with a freind.Be careful around the fan...and check the fan and fan shroud too

[632 Regal]

right, I think the whirring gives it away as a roller or ball bearing issue. if its the steering pump it might be an additional challange to isolate.
Umm...did you check the steering fluid level?