E36 328i engine noise/ticking

[Major]

I bought this car at around 188k, and did an oil change in September around 194k to Castrol 20W50 dino oil (which was probably not a good idea). If I remember correctly this noise started shortly thereafter, but then again the car was still relatively new to me and I might have just been more paranoid about engine noises after an oil change. I've since, in March at 202k, done another oil change to Mobil1 0W40 synthetic, and the noise has continued.

It's worse when the car is warmed up, especially at low RPM's, or just after starting it. I notice it driving next to walls, at traffic lights, etc. It's a clear, almost lashing-type ticking noise, but rises and drops a little bit slower than engine RPM changes (the noise will "hang" while the revs drop). What are the usual culprits here? Engine has no other issues apart from a rich, off-throttle popping which you can sort of hear in the video below. You can more clearly hear the noise on cold start-up, this time it wasn't as bad as usual once it was warm. Maybe it's worse when driven hard, this was a relaxed drive.

[video=youtube]

 

[Nikhil]

10w40 is the correct oil to use and that sounds like hydraulic lifters. Switch to 10w40 but do an engine flush. Let the oil drain overnight.

 

[Nikhil]

The other possibilities could be a leaking exhaust or header flange which could lead to the difference in sound when hot and cold because of expansion and contraction, vanos rattle is also a possible cause.

 

[Major]

The other possibilities could be a leaking exhaust or header flange which could lead to the difference in sound when hot and cold because of expansion and contraction, vanos rattle is also a possible cause.

Thanks for the replies, and it's interesting that you mention that, because I had a few manifold leaks which were welded up, and the header to exhaust gasket was resealed with sealant. Every time I let off the throttle while driving/coasting (especially while the car is still warming up), there's lots of rich fuel popping/burbling noises, and under the car on the driver's side while driving you can here it like a rattle/clicking sound (I'll probably make another video tomorrow morning to demonstrate). I'm decatted so it's much louder. After they sealed it it improved, but it's gotten right back to where it was before if not louder, I just don't hear ticking behind the dashboard like I did with the leaking manifold.

The thing is I don't know why that would explain this noise in particular, because as you heard in the cold start up portion it was bad in the beginning and went away as soon as I revved a bit, which is why I agree on the lifters. When I drive hard around the track they get crazy loud, but that's a feature of these M5x and S5x motors unless you run a lot of oil or a baffled oilpan.

 

[wikked]

You still have the viscous fan? They tend to make funny noises when they get older. Shot in the dark I know.

 

[Major]

You still have the viscous fan? They tend to make funny noises when they get older. Shot in the dark I know.

I do yeah, wanted to fit an electric puller fan before removing it. When the engine's hot and the fan goes into diesel truck mode I haven't noticed the sound getting worse.

 

[328ii]

Ticking noise can caused by injector(s)

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[LPM320]

The other possibilities could be a leaking exhaust or header flange which could lead to the difference in sound when hot and cold because of expansion and contraction, vanos rattle is also a possible cause.

Thanks for the replies, and it's interesting that you mention that, because I had a few manifold leaks which were welded up, and the header to exhaust gasket was resealed with sealant. Every time I let off the throttle while driving/coasting (especially while the car is still warming up), there's lots of rich fuel popping/burbling noises, and under the car on the driver's side while driving you can here it like a rattle/clicking sound (I'll probably make another video tomorrow morning to demonstrate). I'm decatted so it's much louder. After they sealed it it improved, but it's gotten right back to where it was before if not louder, I just don't hear ticking behind the dashboard like I did with the leaking manifold.

The thing is I don't know why that would explain this noise in particular, because as you heard in the cold start up portion it was bad in the beginning and went away as soon as I revved a bit, which is why I agree on the lifters. When I drive hard around the track they get crazy loud, but that's a feature of these M5x and S5x motors unless you run a lot of oil or a baffled oilpan.

I also had that clicking/ticking sound that seemed to be emanating from underneath the drivers side area, but it disappeared when I changed the exhaust system....