Engine tick noise when warm from under the car

[TiesTorN]

It's not really a big problem but I'm curious. What could cause it? makes me uncomfortable hearing that noise.

• Vanos tick? (diesel like sound) is common but that's not my problem. I ordered dr.vanos kit and they are quiet.
• Lifter noise..? maybe... but lifter noise disappears after engine warms up afaik. and it comes from upper side of the engine anyway
• Piston Slap noise..? definitely sounds like it, and a few mechanics I asked said so. but again it should disappear after engine warms up so...
• loosened spark plugs..? I have bosch plugs and I thought maybe... but no, they were tight when I checked.

most people say it's piston slap noise but I think it's highly unlikely because my engine was rebuilt last year down from the block with new cylinder sleeves and new pistons and there is no noise when the engine is cold. also there was absolutely no noise when it was newly rebuilt. noise gradually started after a few months. but it didn't get any worse in the last 8 months.

I'm suspecting sleeves. maybe after the engine broke in, piston rings' collision with metal sleeves while operating causes this noise and the reason it's becoming apparent while warm is because the oil gets thinner? I use 5w40 synthetic oil.

I thought I recorded the sound but it was crap. I'll try to record it clearer and upload here so that you can hear it. in the meantime, any other thoughts? maybe using a heavier weight oil might help?

[TiesTorN]

lol I completely forgot that I even had a topic for this issue. I recorded it clearly this time;

https://www.youtube.com/watch?v=OcwHIx6PPK8

there is that sound like "click click click click..."

it's been almost 4 years since I created this topic. noise is still the same, no change. I lifted the car sometime ago and noticed that the noise is definitely coming from the flywheel area.

any ideas?

[philly98540]

Sure sounds like a lifter to me. Maybe rear most lifter and sound radiating down to bellhousing area? Not sure of course, but that is what I hear from the vid. They can make noise even after warm up.

[Chedley]

Interesting, I have exactly the same ticking noise on my engine, with recently rebuilt heads and timing chain guides.
Mine is definitely coming from the top of the engine, Bank-2 driver side. The same bank that exhibits a sporadic P22 (INPA code 34) error, but no CEL
I suspect bad loose spark plugs, and/or bad Vanos solenoid ?
So I will be replacing the spark plugs with NGK plugs, and refilling with heavier 10w30 winter oil, instead of the regular 5W30, and see if the ticking goes away.

[TiesTorN]

I don't know where it can radiate from, I used a stethoscope to listen and it's coming directly from the flywheel area. besides, I think lifter sound should have a faster rhytym than that.

this is how it sounds from the engine bay;

https://www.youtube.com/watch?v=DYiiIewhgZ4

that clicking sound is not there.

[jicaino]

Exhaust leak

[TiesTorN]

lol my luck... customer's e39 m5 has developed the exact same ticking noise, it's also coming from the flywheel area. owner told us to remove the transmission and inpect the flywheel after listening to the noise himself(realizing that it really comes from flywheel) so we did that and guess what... flywheel had a slight crack on it and some loose rivet apparently but we couldn't see it. the guy we sent it to repair the crack told us there was some loose rivets and he rebuilt them. noise is gone now.

considering my flywheel should almost be the same as an m5 (or maybe the same?) I probably have the same problem. but I'm broke so I won't be doing anything about it for now. it's just a nuisance anyway, doesn't really affect anything. I need to fix oil leaks first

[JimLev]

540 and M5 flywheels are different, indexing tabs are not the same.

[TiesTorN]

doesn't matter, should be a similar issue with mine. that will be my next move when I have the money and the will.

[jicaino]

One of the biggest mistakes would be disassemblying something just to check if you have the same issue as a customer's car just because the noise resembles your noise. (In my opinion, of course)