knocking noise on start up
 

hi, i have a 2002 x5 4.4i, lately iv been noticing that once i have driven my car around for a while and then parked it up for a couple hours and then go to start it again i get this knocking type noise on start up which lasts for a couple of seconds and then vanishes, it never seems to happens on first start up in the mornings, its always after its been driven and then parked up for a while.

any ideas what could be causing this?

Any help would be much appreciated

thanks in advance

My 02 4.4i had this noise that turned out to be WP bearing start to go. I thought it was cam sensor but no.
Are you on your original WP? mine was doing it, started around 55kmiles.

Hi mate, I'm assuming you mean waterpump, if so it has had a brand new one fitted, did your make the knocking noise on start up then vanish after say 2 seconds? And did it happen everytime, thanks for the response

Maybe more, for about 5-10sec, but not all the time.
Did you replace both belts?

No I didn't end up changing the belt, do you think it could make difference? The mechanic did say that the belt didn't look to good, its been booked in to have it changed though!

Not 100% sure if it's the belts but might as well change them if you haven't done it.
Also check the tensioners as well while you are at it.

If it is accompanied by a bit of a rattling type sound it could be timing chain related. Cam sensors start to fail and on start up the timing is messed up so you get the loud intermittent knocking and rattle. They are easy to change as a DIY item and are routine item to replaced at 100K or so.


Mike

cool thanks for your help

[QUOTE=Mikedd;725512]If it is accompanied by a bit of a rattling type sound it could be timing chain related. Cam sensors start to fail and on start up the timing is messed up so you get the loud intermittent knocking and rattle. They are easy to change as a DIY item and are routine item to replaced at 100K or so.

hmmm interesting , i will have to check for a rattle noise the next time it happens, its in the bodyshop at the moment as someone has run a key down the whole side. if it was a sensor causing it then would it not happen everytime i started it? it really only happens after its been driven and then turned off for a couple hours and then restarted, never happens on the first start of the day. thanks for the response

VANOS.

Replace the intake cam sprockets, solenoids, and the one way oil valves that attach to the front of the heads.

Hi j.belknap, do you think that is the problem then? Have you come across this problem with your x5? Thanks

See this link from an E39 forum for another source of startup noise on the M62, and a potential fix.

Probably, and yes. BUT, I am doing the chain tensioner parts at the same time.

These are the VANOS parts...

Cylinder Head Attached Parts [11-15] FOR VANOS
8 non-return valve QTY 2 11121706921 $16.11
9 O-ring13X1,5 QTY 2 11121706927 $0.58

Timing Gear Chain Top [11-25] FOR VANOS
1 Camshaft adjuster unit with imion QTY 2 11367515357 $520.38
2 DISTRIBUTION PIECE ZYL.1-4 QTY 1 11361433660 $54.68
2 DISTRIBUTION PIECE ZYL.5-8 QTY 1 11361433664 $54.68
3 Gasket Steel ZYL.1-4 QTY 1 11361705578 $6.08
3 Gasket Steel ZYL.5-8 QTY 1 11361705579 $6.08
9 Solenoid Valve (SOLV) QTY 2 11367524489 $178.00

EDIT: also add,

VANOS cam seals QTY 6 11311705512

Meltdown, thanks, that is a great link, I'm gonna do that for the sake of some small change out my pocket! A lot of the posts describe exactly what's happening with mine!

J.belknap thanks for the all that info, great help dude, if changing the tensioner doesn't work then I'm gonna show your info to my local indy and go from there!

J beat me to it, but it's definately the typical VANOS issues rearing their ugly heads. It can be anything from the VANOS to the timing belt tensioner. www.e38.org has TONS of information that is still related to the E53 since we share the same motor. More people need to start getting familiar w/ that site.

yeah im gonna try a new tensioner first and see what happens, after looking at that above link its defo worth a go, i got 90000 on my clock so might be worth doing anyway by the sounds of it, i didn't realise how easy it was to change... i thought that the e39 and e53 engine was the same and i think they stopped the m62 in the same year on both the x5 and e39, i think! :confused:

Hi, your better off submitting a new post on this site regarding your problem to get a better response... But my steering is fine and doesn't do what you have described with yours and I also have 20s

Just an update..put a new tensioner in this morning and all has been good so far...started it a few times today with no knocking for once..

good deal man! That VANOS stuff can get pricey... good to hear the tensioner was the cause

Cheers mate..I got a mechanic to do it in the end, and also changed my alternator belt for £40.00, he also looked over the car for me, I'm well chuffed with the result!

update:rolleyes: the knocking is still there sometimes...if its the vanos would i get more of a ticking type noise? the noise i get on start up is the same noise that you would get if you had no oil in the engine! i am due an oil change in a 1000 miles!

topped up the oil the other day with a litre and its just past the max mark and i mean literally just over the mark and iv not heard any knocking since..i bet i didnt even need the tensioner which i had fitted neither..i didnt know you had to run the engine at operating temp then leave it for 5 mins to get the correct reading of the oil levels untill the other day

Wow... Everytime I read the threads you start, its as if I started it. Same noises, same vibrations, and same everything if I had those damn gunmetal 87's! Where the hell did you find those anyway?

Since I know exactly how you frustrated you are trying diagnose your problems:

I have the same noise on a cold start up. It lasts for a second or so immediately after starting. I gave up after countless hours of research with no solid answer. What I found was that its caused by the VANOS and doesn't seem to be a major concern or high priority repair. It sounds wierd buy try searching for "marble(s)" here and bimmerforums.com

http://www.xoutpost.com/bmw-sav-foru...ed-fixing.html

this link is embedded in the above thread:
http://forums.bimmerforums.com/forum/showthread.php?t=1041320


What I have found is that this knock on start up seems to be how my X tells me that it needs an oil change. Its not low or anything, just time for fresh lube.... I change my oil very frequently because when I went to change my oil filter for the first time, I found that there wasn't one. hahaha... what else to do but laugh and flush it. It was completely desolved and turned into a sludgy muddy paste. Knock on wood but I have no leaks, no shakes, no power loss, and no knocks other than the occasional marble clack on start up.
Changed the oil and problem solved every time. Noise comes back usually around 3 or 4 thousand miles
Unfortunately I just became a member of the 6 digit mileage club.


I stumbled across the thread below looking for the link above for you. I have no idea what this guy is talking about or how a rubber bushing can make an engine knock but I thought you might wanna take a look?
http://www.xoutpost.com/bmw-sav-foru...can-sound.html


Completely wrong thread, but did you ever replace your flex discs?

I'll say there are at least 2 posts in those thread plus I can add from my own experience, Mobil-1 0-40 helps reduce even eliminate the start up rattle on my 4.4i as well.

Yes, I don't know if it's VANOS is Priority or not, but if it was were bushings then why would it only do on cold start-ups and only for few secconds?

Vanos rebuild is in your future. Probably cost around 1200 in parts. I wonder if the new parts are designed better or the same

Sadly, even after replacing the VANOS parts, it can eventually happen again. There is website www.drvanos.com, but I've written him and he doesn't do the M62 units, nor does he have any intentions to. The 3.0 X5 guys are in luck, but not us V8 owners. This is why I intentionally bought my 7 as a 98...no VANOS, but since I didn't have a choice with the X, I also religiously use Mobil 1 0w40 in both V8's.

whats the difference for the engine when using 0w-40 instead of bmw synthetic(ibelieve5w-30). is it thicker,thinner,please enlighten me.

Thinner when cold, thicker when hot.

The thin end of the scale (0) means that there is less protection from the oil on startup, but that the oil can be pumped easier. The high end of the scale (40) means the oil can better stand up to high speed runs across the desert, for example.

What JCL said :) The stuff is like water at startup, but gets nice and thick once warmed up. VANOS rattle is basically an oil starvation issue until pressure builds up and stops it, so going thinner at startup is really the only solution. I've heard of people replacing the timing chain tensioner as well, but I haven't had to cross that road yet.

I just ordered the tensioner for shits and giggles, see what that will do with an oilchange. Next year will be vanos rebuild. Thanks for the info jcl & m5james. Thanx for the list of parts jayb

I hear the same noise sometimes after it sits for awhile . I was wondering if it could be bearings of some sort in the lower engine

Not bearings, just a typical VANOS rattle. Welcome to aging M62TU engines.

wonder how many folks solved the start-up rattling after using 0-40 oil? does it last long?

The problem James is that it only has 55,000 miles on the clock.

Even with 55k the vanos problem can show it's ugly head. Try a new chain tensioner like donone69, but it's most likely the 1400.00 vanos rebuild. I don't believe performance is affected though

I've got a customer/friend who's got a 750iL with only 80k on it...but it's a 95. It's got a grocery list of replacement needs, everything from dried and rotted seals to worn out suspension bushings. Having only 55k on your 01 is awesome, but seals will still wear over time, not just use. Did you mention what oil weight you use?

No problem bud!

Also add VANOS cam seals x6, P/N: 11311705512

I use the recommended oil. I am going to have it checked out by a friend who works at a BMW dealerership and hopefully it is just the tensioner as Justin said.
Thanks for the advice.

hello mate, i don't get the knocking noise anymore, i previously topped up the oil with a litre, well just under a litre and it was fine, after i topped it up i just use to get a very vague knocking on start up probably 2 to 5 times a week, it was much better and could barlery hear it at all, it took the oil level to just after the max mark on the dipstick, it was due a oil change which i had done 2 weeks ago at my indy using 10/40 oil and now i cant hear a thing ever, runs smooth as anything

as for the flex disc, it looks new so iv not changed it and the vibration is still there:dunno::banghead::banghead::banghead:, it drives me insane

Old thread bump, but this is related information - Timing Chain Tensioner Replacement (M62TU) - Bimmerforums - The Ultimate BMW Forum

I definitely think 0w-40 is the best supplementary solution here...

I have the same noise in my e36 when it is a little low on oil. After a top off, it goes away. I would suggest checking the oil level and adding to the max line before ever even thinking about vanos or other mechanical repairs. I would guess this is the issue more often than not.

I fixed a customers E34 530i who had valve noise and everyone on the boards said to overfill the crankcase to stop the noise. I still don't see how that made sense since all the oil is pumped up to their anyways, just like it is here with VANOS. Proper weight of oil is probably the safest bet, and being topped up, that's just something that is expected. I always carry an extra quart of oil with me and check it every other time or so when I get gas.

I agree, but you can't assume anything is expected here as you really don't know what someonce else knows about cars. Just saying the noise on start up issue is more than likely an oil issue and not a vanos or mechanical issue.

Once in a blue moon mine still makes the rattling noise if it sits for a while, and I've been using 0w40 for as long as I can remember. It's just something I've gotten used to.

Nice signature, by the way. Dead pixels...:rofl:

:thumbup: I good a good laugh myself...and it's ironic how true it is.

sorry to sound thick!
but what is vanos, please?

Google and Wikipedia are your friends ;)

http://lmgtfy.com/?q=BMW+VANOS
VANOS - Wikipedia, the free encyclopedia

Thanks for the info.

amazing find im having the same problem now:thumbup:

what kind of fuel are you using?

What does fuel have to do with valve train noise? This isn't an engine knocking issue via gasoline. Besides, we should ALL be using a good quality 91+ octane regardless.

Misread the thread title sorry. I don't know why I associated the word knocking to shaking. Guess it really has been a long week (and its only Tuesday). Had a shake/vibrate on start up because I was a fool and used 89 for a little bit.
Anyways, this is not even the topic at hand. Basically no one pay attention to anything I'm saying in this thread lol.

It'll run on 89, but it'll back off the timing to compensate for the lower octane gas mileage, basically offsetting any savings in gas by producing less HP and lower gas mileage at the same time. My engine in the 7 is a little different, but it HATED it when I accidently filled a whole tank of 87..bucked, stuttered, etc.

James,

There was a letter in Roundel where a reader suggests one way to help maintain your Vanos system is to replace the failure prone Vanos gear bolts. He says that these bolts tend to come loose from the cam gear and eventually sheer off resulting in the destruction of the timing chain, valve cover, cam gears, etc. Thus, the complete Vanos overhaul. He suggests that to prevent this, you simply need to replace the 12 cheap bolts before failure. He goes on to say that a friend with an e46 M3 had the Vanos rattle and when they inspected it, 5 of 6 bolts on the intake side were already sheered off and the 6th was loose.

What do you think about that?

A pretty much massive failure like that happened to a customer of mines 99 740iL to the point where we rebuilt the engine with the help of his son. It was a headache while the engine was still inside the engine bay to say the least, but he wanted to do it at his home.

The bolts may be cheap, but it's sometimes getting to them that can be the issue. I have a pair of wrenches welded together to hold the cams gears in place to make sure to not screw up their timing during disassembly. Here's a couple quick links for those who like stimulation via car porn...take it off baby! :)

So... My car has loose VANOS bolts.... (pics) - BMW M3 Forum.com (E30 M3 | E36 M3 | E46 M3 | E92 M3)
DIY: Fix your lose VANOS bolts! LOTS O' PICS! - BMW M3 Forum.com (E30 M3 | E36 M3 | E46 M3 | E92 M3)
YouTube - BMW E46 M3 VANOS bolt failure #1
YouTube - BMW E46 M3 Vanos bolt failure #2

...and you said "who cares" about a few VANOS issues ;)

Well, it sounds like a few bolts cause the most issues, so replace them once with the updated bolts and all is good, right?

No because the seals go out as well. From my understanding into their failure (other than the bolts) is that they have something like an anti drainback in there and the rattle is from them being dry at startup. From the replacements that I've done, it requires a few special tools to make sure the timing isn't messed up, clips, etc. The V8 (single and dual) VANOS are different than the I6 version. To be honest, I've never had to do an I6 one as of yet.

That wasn't my experience. My best mileage on the highway was 27 (imperial) on my 3.0, measured several times from fill up to fill up, and that was all on AKI 89. That suggests that in my case the timing was not being backed off, which would have increased fuel consumption. Engine started and ran great. All I got was the savings, not that it was enough to matter, only about $0.30-$0.40 per gallon. AKI 87 did cause a slight reduction in performance in my case.

It will be different for every owner, as fuel varies so much across North America. In some cases the local 91 is crap, and will still cause problems. Other locations have better fuel, and 89 is fine. Sweeping statements that owners must use 91 or 92 AKI or lose power just aren't true. Owners should use an AKI rating sufficient for the engine (but not higher).

I know how my 7 reacted the one time I did it, but as I mentioned, my engine I a little different than most.

My sweeping statement is based off what's written on the fuel door and/or the owners manuals in my cars. I do agree though that a cheap brands best gas could compare to a quality brands lowest grade gas. Maybe its just placebo for me, but I try to use the Top Tier brands on the BMW's and the bike, preferebly from a station that has in individual pumps for each grade so I don't fill up with however many gallon of 87 in the lines that the previous person used before me.

I wasn't aware that you put so much stock in BMW's recommendations :rofl:

Nothing wrong with Top Tier, but don't trust it to be more than it is. It doesn't cover quality in terms of either actual AKI, cleanliness, water content, or most additives. It only addresses deposit control additives, which is a very narrow spec.

Im selective in following their recommendations, some I follow with experience and others based on common sense.

BMW suggests (not demands) to use a quality higher octane gas, but that make sense with any performance tuned vehicle. I learned about the benefits of the proper octane when I supercharged my Tacoma as it pinged like crazy on lower octane gas but it stopped when I ran premium. My 7, while not FI, reacts the same way.

BMW demands (not suggests) to never change the transmission fluid, and in servicing situations to save the drained fluid and reuse it....that's just ignorant.

I take all of BMW demands and recommendations with a grain of salt.

Can any one else Say that keeping the oil maxed and changing to 0w40 has help with the start up knock?