My car doesn't sound like it should

Thu Oct 13, 2005 11:19 pm

I'm really fed up with the noise my car makes. Everytime i hear that glorious 6-pot purr of any other beemer run by (including the other 325 tourer i just sold), i wish my car sounded like that, but it doesn't - not at all.

I've got a 6-branch manifold, std centre and Scorpion rear box, but i dont think any of them are spoiling the sound. I have really noisy injectors (i think) that make an awful ticking noise, which more or less over-powers any other noise i can hear sitting inside the car. It kind of chuff-chuff-chuffs along rather than purrs.

Every other 6-pot E30 i hear sounds great, but mine sounds pants.

It's the one thing that i really hate about my car.

So what can i do to sort it?

Thu Oct 13, 2005 11:24 pm

Hmmmm.
You sure you haven't got a worn camshaft?
It has a habit of making a 325 sound like a 2 ton sewing machine......

Thu Oct 13, 2005 11:25 pm

it'll be the centre section.I took mine out completely.It sounded awesome.Not any louder just nicer.

Thu Oct 13, 2005 11:26 pm

Pete, is this you who i met at the Surrey rolling road?

Why sell the Tourer, such a nice car

Fri Oct 14, 2005 8:16 am

Dan - i just put a dBilas cam in - brand new. It's made a difference to the idle noise, but done nothing above that sound-wise. I may get my tappets checked again, though they've been done twice since the new cam was put in (new head also btw).

Jon - it was me you met, yes, but the car i sold was my other one - i still have the one you saw at the RR day.

Fri Oct 14, 2005 11:03 am

just registering my interest as I may have the same problem, above 1500 rpm a kind of ticking, best I can escrible is like someone flicking through a pack of cards - sounds like its coming from centre consol area? frequency increases with RPM, anoying!

In mine I cannot really hear the noise outside, or with the bonnet open (or a cannot distinguish it from injector noise...

Doug

Fri Oct 14, 2005 12:05 pm

haven't you already had your injectors ultrasonically cleaned Pete?
Mine are bloody awful as well as I've only recently done the valve clearances for this very reason!

Fri Oct 14, 2005 12:23 pm

doug325i wrote:just registering my interest as I may have the same problem, above 1500 rpm a kind of ticking, best I can escrible is like someone flicking through a pack of cards - sounds like its coming from centre consol area? frequency increases with RPM, anoying!

In mine I cannot really hear the noise outside, or with the bonnet open (or a cannot distinguish it from injector noise...

Doug

Are you sure your starter motor is not still engaged?

Fri Oct 14, 2005 12:32 pm

A slight blow in the exhaust manifold gasket causes a TICK TICK sound, most annoying, had one on the car before the conversion and only discovered what it was when I took the manifold off.

HTH, Mark.

Fri Oct 14, 2005 12:56 pm

Thanks for all your thoughts on this one guys. It's been driving me nuts!

Fozzy - Exhaust manifold has been changed twice in the past year, so it's not that.

Jim - that's next on my list. I've bought a set of injectors from Scott with the aim of getting them cleaned up and swapped into my car to see if that solves it. In theory though, i gather the injector noise is down to the solenoids and hence ultrasonically cleaning them wouldn't necessarily make a difference - or am i missing something?

Doug - i've been watching your other thread on a similar topic. My noise is most definately audible under the bonnet and is apparent even at tick-over. I'd recommend the blu-tack noise that someone else tipped you off about - it really works! If you can, seal off the bottom end of the steering column too.

I'm 90% convinced i've got at least one really noisy injector. Having replaced the complete head, cam, set tappets twice and replaced exhaust manifold gasket twice, i cant see what else it can be.

I'm almost at the point of paying through the nose to get someone who knows these engines inside out to check it over. My local BMW dealer service manager listened to it and suggested it was tappets, but i dont buy that as the noise has never changed despite everything i've done to the car.

Please keep the suggestions coming! I'll maybe try taking a vid/sound-clip of the engine bay to see if i can capture the noise to post on here.

Fri Oct 14, 2005 1:00 pm

Well if I change mine before yours pete (got some M30B30 ones that might get fitted with megasquirt) I'll let you know if it changes the sound, it's hard to describe a sound in words but it's more of a flap than a tap lol!

Fri Oct 14, 2005 8:57 pm

Cheers Jim.

Anyone know any good places to send injectors to be cleaned?

Perhaps i should start another thread for that Q.

Fri Oct 14, 2005 9:01 pm

I did a search on google a while ago, I found the places that listed prices quoted for 4 injectors.....

I'm gonna give the place who did my engine recon a ring on Monday see if they do it, or at least recommend somewhere that can, you could possibly post them I suppose Pete.

Sun Oct 16, 2005 7:08 pm

one day when i had a 325i, i had a noise like urs, sure u can hear the injectors clicking, etc, but if you've narrowed it down to the tappets... try this, what a bmw dealer did for my car when i had this problem - the oil pipe that delivers oil to the top of the engine might be blocked therefore starving the tappets of oil hence the clicking sounds, take the rocker cover off and u'll see it wind around the tappets, the pipe will have little holes in them, OR as mine was, full or crap so nothing was even getting to the tappets. sadly Ãƒ”šÃ‚£80 off bmw

Sun Oct 16, 2005 8:05 pm

If its coming from the front of the engine, the cam belt tensioners have a tendency to start tapping. I bought a cheap 325i to do an engine conversion with once. Had a terrible knocking sound once i started to drive the car around, so bad that i held back from giving it the boot due to embaresment from the noise

Found out once i started to strip the front end of the engine down completely that the oil pump was stuffed. The reason was oil starvation i recon because the sump plug had had an insert fitted, so some previous owner must have stripped the thread causing near complete loss of oil

Sun Oct 16, 2005 8:47 pm

deian wrote:one day when i had a 325i, i had a noise like urs, sure u can hear the injectors clicking, etc, but if you've narrowed it down to the tappets... try this, what a bmw dealer did for my car when i had this problem - the oil pipe that delivers oil to the top of the engine might be blocked therefore starving the tappets of oil hence the clicking sounds, take the rocker cover off and u'll see it wind around the tappets, the pipe will have little holes in them, OR as mine was, full or crap so nothing was even getting to the tappets. sadly Ãƒ”šÃ‚£80 off bmw

They ripped you off then mate!!

I bought a new oil spray bar on Friday, Ãƒ”šÃ‚£11.

Sun Oct 16, 2005 10:32 pm

A couple of interesting new takes on this.

WHen i fitted the replacement head, i took particular care to ensure the oil spray bar wasn't blocked - cleaned all the holes out and blew them through one by one, so i dont think it's that. Can you run the engine without the rocker cover on without oil splattering everywhere though? I know it will run a bit rough because of it not being airtight. I've had a quick peep inside with the filler cap off and i must admit, i couldn't see much oil being thrown about. It didn't look dry though.

I've had the cam-belt tensioner changed about a year ago when i had the cam belt-done, so hopefully it wont be that.

Hadn't considered the oil pump though - that's something that's not been touched since i bought the car. Could be that i'm not getting enough oil pumped to the top end perhaps?

How easy is it to replace an oil pump then? Never done one before and i'm clueless as to where it is even.

Sun Oct 16, 2005 10:55 pm

not a small job mate, the cam belt needs to come off to start, its in the front of the block and is run off the crank. Although they only cost around Ãƒ”šÃ‚£40 from Euro

Sun Oct 16, 2005 11:24 pm

buy a stethoscope, or use a long handled screwdriver, place one end of the screwdriver / stethoscope on each injector. Place your ear against the other end of the screwdriver, you will be amazed how you can trace the source of your noise...

Mon Oct 17, 2005 8:19 am

The way to check if its injectors is to drive in third and get it to 3k rpm (65-70 mph) then let go of the accelerator if the ticking stops then its the injectors, if it doesnt then you have a worn head. How brand new is this head exactly?

You need to sit at he lights with the windows down in a S14 powered car and hear ticking!

Andrew

Mon Oct 17, 2005 9:20 am

DanThe wrote:not a small job mate, the cam belt needs to come off to start, its in the front of the block and is run off the crank. Although they only cost around Ãƒ”šÃ‚£40 from Euro

That's on a M40 engine. We're talking about a 6 pot here aren't we?
M20 pump lives right down in the front part of the sump.
Need to lift the engine a litle and remove the sump to get at it.

Mon Oct 17, 2005 10:30 am

Pete - I will see if I can get a sound clip organised later, Then we can compare noises... Somebody may recognise it.

Doug

Mon Oct 17, 2005 1:17 pm

Andrew - thanks for the tip - i'll try it on the way home tonight. Can you tell me what the theory behind this is though - aren't the injectors still squirting fuel even on the overrun?

Brian - yes, it's an M20 325. Thanks for the guidance - made me feel a bit better about getting this done. Do they deteriorate with time? Is there any way to tell if they're on the way out?

Doug - damn, i forgot to do my sound clip - i'll try this evening.

Mon Oct 17, 2005 1:23 pm

Just had another thought about the oil pump - i've noticed my car does smell of hot oil after a drive to/from work, though i dont appear to be loosing any.

Wed Oct 19, 2005 10:57 am

Hi Pete,

I've just posted on this exact topic (before I saw yours D'oh!)
My C2.5 sounds like it has the same problem as your car - yet I have a standard 325i Touring which is MUCH quieter in comparison!

I don't notice the 'ticking like a sewing machine' noise much above 3000 rpm - but at that speed its probably drowned out by everything else.

The performance of my car still seems quiet lively - I'm even considering having a rolling road session to check its BHP (claimed to be 190bhp when new) - on a side note anyone know a rough guide price for a RR session?

Sorry I've got nothing useful to add - just thought I'd join in!

Regards, ProfDMW

Thu Oct 20, 2005 8:42 pm

Hi Prof,

Just read your other thread in the hope it might have given me more clues as to the cause of mine! There was another thread too recently about what appeared to be the same issue.

I'm still no nearer sorting mine sadly. I'm waiting for a set of replacement injectors to come, which i'm hoping to get professionally cleaned and tested before fitting because this is my first suspect - one or two noisy injectors. Second culprit is oil starvation on the cam/rockers due to a oil pump not doing what it should. I think i've more or less ruled out tappets (adjusted twice recently), worn cam/rockers (replaced recently) and the exhaust manifold gasket (replaced twice recently).

I'm going to try the stethoscope or screwdriver trick this weekend to try to narrow it down. Failing that, it's going into the garage for them to sort as i'm fed up with it!!

Thu Oct 20, 2005 9:05 pm

Pete,

It has been suggested to me that the noise may be from a dodgy centre box - sound does seem to come from this direction... I too have just adjusted the tappets with no success and Im on to the exhaust gaskets next as need to replace the heat shields anyway.

O - Have you checked your Distributer cover is not loose? worth a look, mine was rubbing on the fan on ocasions.

Anyway keep us informed - your miles ahead, you havent got that much left to check !

good luck

Doug

Sat Oct 29, 2005 4:51 pm

What about from idle, with the bonnet up. I can hear a ticking sound. I don't remember my mum's old 86 325 making that sound!

Sat Oct 29, 2005 6:35 pm

doug325i

Your theory about Center Box could be the source of ticking noise. I am interested to know more.

Infact I think I too have this problem and I am suspecting the Center Box, and contemplating to change the center box to an original or a heavy box.

my current cetner box looks thin and cheap so i assume the noise coming from there. When I drive close to a wall, I can really hear the noise is coming right beneath me, and not from the front.

cheers

Sun Oct 30, 2005 12:05 am

PeteE30Tourer wrote:Andrew - thanks for the tip - i'll try it on the way home tonight. Can you tell me what the theory behind this is though - aren't the injectors still squirting fuel even on the overrun.

Have you tried this yet? The injectors are cut off on over run with no throttle, untill the revs drop to about 1800(?) RPM.

Tue Nov 01, 2005 7:57 am

Brianmoooore wrote:
PeteE30Tourer wrote:Andrew - thanks for the tip - i'll try it on the way home tonight. Can you tell me what the theory behind this is though - aren't the injectors still squirting fuel even on the overrun.
Have you tried this yet? The injectors are cut off on over run with no throttle, untill the revs drop to about 1800(?) RPM.

Tried it last night - both in gear (under load) and in neutral - made no noticable difference. Whatever the noise is, it's getting gradually worse - either that or i'm just getting more honed into it. The car's going into the garage tomorrow to get the clutch master and slave cylinders changed, so i'll aks them to dig around with their stethoscope. I've also just sent off a spare set of injectors to be ultrasonically cleaned so i'll swap those in once i get them back.

Wed Nov 02, 2005 9:58 pm

Pete, Im allmost sure im suffering the same problem. I think mine too is getting worse, Can't be sure but I do remember ocasions when i couldn't hear it in the past, now its all the time even when the engine is colder...
My imagination is going crazy thinking of all the places it could be coming from|!

Di the garage shed any light on the subject? Im almost at the point of buying in another cylinder head and changing them over - just in case it inadvertantly cures it!

haffeel; Please let me know if you do change the centre section over - would love to find an easy fix to this annoying noise.

Thu Nov 03, 2005 8:10 am

Hi Doug,

I'm not sure whether mine is getting worse or if i'm just getting more tuned in to the noise and hence notice it more.

The garage had a good poke around with their stethoscope last night and couldn't really put their finger on it. They thought it was tappets with perhaps a little noise from the small end bearings around 3k revs. When i get a dry weekend, i'll have a go at setting the clearances yet again. Thing is, i cant believe it's the tappets as the entire head, cam, rockers etc was swapped over earlier this year and the tappets were set up twice afterwards with no difference in the noise at all.

If this fails, i think i'll give up and turn up the stereo instead to drown out the noise!