540i Engine Whine and Noise During Idle

[ttgxc]

My 540i currently has 172k miles on it. I have noticed over the last few months clicking/tapping noise during idle when you are outside next to the car. Last week I had a small oil leak and brought the car into my indy mechanic to address both issues. He determined the PCV vent valve was leaking causing the minor oil leak and replaced it. He then took off the valve cover to inspect the timing chain guides. He determined there are no issues with timing chain guides plus the chain was not loose and he did not see any other issues. I got the car back today with it still the same during the idle, now it also has an engine whine that was not there before. The whine sounds like a super charger and increases with noise when the rpm's climb. The car runs and drives with no issues. I have added video.

[edjack]

He should have addressed that noise: it's very obvious! My guess would be a dry idler wheel. Get it fixed posthaste!

Find a better mechanic.

[ttgxc]

He has been working on the car for the last 9 years and doing a fine job, so this is a bit frustrating. Waiting for Monday to call him. I wonder if the whine noise has anything to do with the work he was doing on the car. It wasn't like that before.

[JimLev]

The chain guides almost always look good when viewed with the valve covers off.
The small pads on the cam to cam tensioners will last for a long time.

If the 3 main guides have never been changed you might consider dropping the lower oil pan to get a better look at them.
The bottom of the center U guide is the one that gets most of the wear and can't be seen from the top.

[R Shaffner]

I agree -- I'd look at things being turned by one of the two serpentine belts first. (Tensioner pulleys, alternator, power steering pump, AC compressor, water pump.)

Does the sound change when the AC is turned on or off? How about when you turn the steering wheel? If so, take a closer look there.

Are you familiar with the metal-to-the-ear approach? Take a long metal rod or metal pipe, and VERY CAREFULLY put one end to your ear and the other on the body of a component that has a rotating part. If the part is good, you'll hear the whir of good bearings. If it is bad or going bad, you'll hear a noise that sounds rougher -- the amplified version of what you're hearing now.

You MUST be careful because the fan belt, fan and other things are all rotating, and you DON'T what the tool, your fingers, or your clothes to touch or get caught in any of the moving parts. If you're not confident you can do it, please don't try.

I've used a metal pipe, a long breaker bar, or several long 3/8 socket extensions linked together.

I know it would be an odd coincidence for one of those things to go bad right after the mechanic did something else, but stranger things have happened. I have trouble seeing how changing the CVV (PCV) or removing/replacing a cam cover would cause that sound.

You could also use the metal-to-ear test to listen to each cam cover, up front by the chain. Just to make sure they sound they same. If they don't sound similar, your mechanic might have screwed something up.

Good luck and be careful!

[ttgxc]

Thanks for the tips. I will follow up with what I find out.

[ttgxc]

I wanted to add an update. It was discovered that the center timing chain guides were shot. All the timing chain guides, tensioner and other related parts were replaced. Everything seems to be good now *fingers crossed*

[Mach540]

Who did the work for you?
If you don't mind putting on your flame suit, what did it cost you? (People will always say you overpayed)

[ttgxc]

My local Euro mechanic. It cost me $2900.00.