Gentlemen this is my new issue. Im thinking water pump?
As soon as i stopped filming the noise stopped as well. It does return upon starting the engine.
01-05-2010 12:18 PM
Sounds like oil not getting to one of the lifters at idle, something in the upper drive train. When rpm is raised making the noise seem to go away. The extra oil pressure dampens the slap sound.
My e34 made this sound every winter. I used esso xd 30 diesel oil one summer to clean out the engine and didn't make any noise the following winter.
01-05-2010 12:30 PM
Get a long screwdriver (> 12") place the handle on your ear, and the tip on the valve cover, water pump and other areas. You will be amazed at what you can hear. This will allow you to pin point where the problem is coming from.
-OR- Spend < $20 on a mechanics stethoscope.
01-05-2010 02:08 PM
If its oil pressure thats not good
01-05-2010 02:20 PM
Definitely not a lifter. Sounds more like a noisy injector to me. Hard to tell on the video though, it also kinda sounds like an electrical arcing a little too.
First thing to do is to take off the plastic cover, as well as the ones over the coils. Those really dampen sounds and make it hard to pinpoint locations. Then as Max_vq suggested use a screwdriver handle or a stethoscope.
01-05-2010 03:09 PM
Any codes ? Check engine light on? I have an obd11 scanner and code reader. If intrested.
01-05-2010 09:21 PM
Haven't scanned it. No check engine light tho.
It does sound like an electrical spark.
01-05-2010 10:06 PM
Check for lose spak plugs!!
01-06-2010 12:39 AM
Originally Posted by parm
Sounds like oil not getting to one of the lifters at idle
This. Could be a bad lifter, clogged passage or a dying oil pump. Could be worth trying different grades of oil, not sure which though. A thinner oil would get through clogs easier but thicker oil would make it easier to maintain higher pressure and stay in the lifter easier.
01-06-2010 01:30 PM
One guy on bimmerforums/bimmerfest had a noise like this and it was a LOOSE SPARK PLUG. You may want to check it out ASAP...
01-06-2010 01:38 PM
I've had a loose plug on mine, and it didn't sound like that because the plastic cover over the coils muffled it. But ya never know, so it's worth a check. You'll know very quickly just by pulling the plastic and having a listen.
01-06-2010 07:31 PM
Sounds like an injector to me, the valve noise would be louder than that.
06-15-2010 12:28 AM
seriously I get the same noise but only when I track it (hard driving) as soon as I get back to normal driving it stops I've talked about this problem to Dr Vanos and they are almost certain it's a lifter not holding it's oil. (my car 1997 M3) mine are hydrolic lifters so I was told that under harsh driving they discharge and thats why I hear the rattle noises. As driving gets normal they build back up and rattle stops. Is this something you hear all the time? if so then you most have mechanical lifter which would rattle all the time.
if it's the lifters then it's no dangerous but very annoying.