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Discussion Starter · #1 ·
I still didnt sell my bmw because i decided to take it to GMR before i sell it and see what it can do and here is what happened.

Went down the downhill run, stayed in 3rd mostly at 3k rpm for about 13 minutes and when i got to the bottom of the hill, i noticed some knocking sound. So I parked my car, opened the hood and the left and right sides of the engine were knocking. The sound is hard to explain but it sounded like knocking or valve slapping). At first I thought its my valve train, then it kinda sounded like the timing chain was hitting something.
I let the car rest for like 5 more minutes, started up and the sound was still there. Because i was all the way down, i still had to climb all the way up to the top parking lot. For most part I took it easy, stayed at like 1.8 2 k rpm. Then pushed it a little bit to see how the bmw responds and everything seemed fine. i parked at the top, got out and sound disappeared completely.
20 minutes later i raced 2 civic with minor suspension mods and both turboed. We raced for like 15 minutes, i stayed 2nd and 3rd gear at about 4 to 5k rpm and when i parked to take a rest, there was no knocking sound at all. (btw the civic delivered my ass to me)

IF it was by rods (bearings), valve train or timing chain knocking, i think the sound wouldn't have just gone away after i pushed my car, right?

What can be the problem?

Thanks


BTW im running 91 octane
 

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Any number of things like over-revving it on the down hill. Low oil level.
 

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Have you been using any engine cleaners, valve cleaners, etc? Anyting other than oil?
 

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Freude am Fahren
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Do you know what the M62 lifter sound is?
 

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Discussion Starter · #5 ·
Have you been using any engine cleaners, valve cleaners, etc? Anyting other than oil?
Nope, never used any additives before and the oil in the car is Mobile 1 synthetic.

Any number of things like over-revving it on the down hill. Low oil level.
Just like i said, i stayed at around 3K rpm, that isn't considered over reving, now is it :)

But oil level was right at he lowest point on the dip stick, so i guess it could be the oil
 

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Freude am Fahren
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no not really because im not a bmw guru but i know how a healthy m62 sounds like and the sound wasn't good
A light ticking from the valvetrain is "normal" and it's due to poorly designed lifters.
 

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I dunno. My car has 113k on it, and the engine is as quiet as an electric motor, cold or hot. I've never had lifter noise, and I don't drive like a Geezer. I also use Castrol GTX 20W50.

The only Mobil 1 you s/b using, as I've read, is 0W40. That is apparently the only one formulated for BMWs.
 

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Discussion Starter · #11 ·
Chain slap? Replace your tensioner and cross your fingers.
yeah, that's what i have been thinking. Also when the time for oil change comes, i will drop the oil pan and see how its doing, maybe my timing chain plastic guides are going out (Even though thats a common problem with the VANOS m62)

A light ticking from the valvetrain is "normal" and it's due to poorly designed lifters.
Actually my engine doesnt have any knocking at all, its even quieter then my friend's accord v6 but that night it was really KNOCKING.

After all i think it could be just the low oil level. Will do an oil change soon andtake it there again and see how it does.
 

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Change your oil and check your spark plugs. It wont hurt. The only cause I can assume from the information you have given is that when you are going down hill for a long time you are swinging all the oil to one side of the engine, starving the other side since you were running low on oil. When you went back up hill you swing it back to the other side.. Report back after you change your oil.
 

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A light ticking from the valvetrain is "normal" and it's due to poorly designed lifters.
So quick to attack the BMW engineers. All hydraulic lifters make some light ticking or tapping.

Poorly designed lifters you say. What kind of noise does a poorly designed lifter make?

And what specifically makes the design poor? I'm talking about the lifter, what part of it is wrong?

My lifters make the same light tapping sound they did 150,000 miles ago. No louder and maybe even a bit less sound after 150K miles.
 

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Discussion Starter · #14 ·
Change your oil and check your spark plugs. It wont hurt. The only cause I can assume from the information you have given is that when you are going down hill for a long time you are swinging all the oil to one side of the engine, starving the other side since you were running low on oil. When you went back up hill you swing it back to the other side.. Report back after you change your oil.
That makes sense, thanks :)
I added 1 bottle of oil to the car just to play it safe till i actually do the oil change.
 

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That makes sense, thanks :)
I added 1 bottle of oil to the car just to play it safe till i actually do the oil change.
Don't do that unless you are down a qrt. Do not over fill.
 

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A light ticking from the valvetrain is "normal" and it's due to poorly designed lifters.
Do you know where your lifters are located, and how they work in general?
 

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Discussion Starter · #18 ·
something really interesting happened.
So before i had a small oil leak for the past month and i had no clue where its coming from. it was on the bank 2 (the air intake side) and it seemed it was coming somewhere from middle of the block but i couldnt really figure out where it was coming from.

Then yesterday i added the bottle of oil (Now the level of oil is between full and empty) and the oil leak stopped.

Anyone can give me any explanation why??
Thanks
 

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My 2000 540I M-Sport has had a ticking sound in the valvetrain on and off ever since i bought it almost a year ago. Its a daily driver, not tracked, driven like it was built to be, fast with reasonable limits. with 146XXX, i've replaced all the lifters, all chain guides, and both chain tensioners in between the intake and exhaust cam (the main tensioner was fine). I inspected and flushed the oil ports in the head leading to the lifters to insure no debris blockage. My oil-pump passed my visual inspection (mounting and hardware intact) and seeing no trouble code has popped up, it seems i am running sufficient oil pressure. i ran the bleed-down procedure to remove any air from the lifters after installation ... and i still have a ticking (borderline knocking) in my valvetrain. I am now suspicious of my valves (whether springs, bad valve guide, valve lash out-of-adjustment, not sure). The car performs fine w/ the exception of an embarrassing knocking when pulling up next to some fine trim.
 

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Sounds like your knock is quite loud.

Have you tried a compression check?
 
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