[Hiffy]

Hi,

I have this really irritating rattle/jingling/chattering sound coming from the engine bay as i'm driving along. it comes in at around 2000 rpm when the accelerator pedal is around a quarter depressed... basically enough for keeping the car going at a constant speed... If I take my foot off of the accelerator it goes away and if I press it harder so that the engine is under load then it goes away...

When I'm at motorway cruising speeds it sounds like a really low ticking sound almost like pinking... As soon as my ears pick up the sound my brain starts to amplify it and then no amount of volume on the stereo will drown it out... By the time i reach my destination its driven me nuts...

A bit of history:
the cars a 51 plate 150bhp 320D, manual.
has 109k mile on the engine.
its been doing it ever since I bought it, which was 3 months ago.
previous owner had the turbo changed over a year ago.
since I got it I cleaned out the EGR, changed breather filter, oil and oil filter, air filter, checked swirl flap which seemed solid (gave them a good wiggle and there was no play).
it does chuck out a cloud of black soot when i floor it (more so when i've just been pottering around town), but some say this is normal. Is it?

Thanks.

 

[xXNealXx]

Have you checked for any air leaks?

 

[Hiffy]

Have you checked for any air leaks?

thanks for the reply. do u mean the intake, from turbo to the intake manifold? the intake manifold end seemed ok, all the pipes were on properly. didn't look on the turbo side though. i'll add that to my list of things to check. the little vacuum hose under the manifold were also ok.

driving home from work today i noted that at motorway speeds it sounds higher pitched and sounds like its coming from the dash or under the car. but at town speeds it sounds lower pitched and like its coming from the engine bay.

 

[addy]

Hi just wandering if you managed to locate the problem with your car i have exactly the same problem and and im running out of things to try ie removed swirl flaps/fit new maf sensor/blocked off egr its so annoying i cant get it to make the noise by reving engine in neutral its mainly when accelerating and on motorway and does sound like its coming from under the dash i can make the tinkling noise go on and off by releasing accelerater pedal slightly and pressing again the noise is definately coming from the engine as it can be plainly heard when window is down thanks.

 

[Hiffy]

hi mate,

still not got to the bottom of mine yet... i have some more infor on the symptoms though... mine starts off almost in audible if i've just been toodling around town then hit the motorway... however, after a few minutes of motorway driving it seems to get louder... if i drive the car hard then it seems to get louder sooner...

mine almost sounds like a whistling, which leads me to think that one possibility could be that one of the injectors is clogged up... if there's muck built up at the tip of one of the injectors then the high pressure can cause it to make a whistling sound... it also leads to uneven fuel spray patterns which causes a louder combustion sound, and more unburnt fuel which can be seen as puffs of black smoke when you boot it after a while of driving gingerly...

because it fits this pattern of symptoms i'm concentrating on the injectors at the moment... it seems like it could be some kind of fueling issue... anything before the high pressure fuel rail would likely have been picked up by sensors and flagged by the ECU... i'm trying a few different injector cleaners, so far went through a bottle of redex and currently trying wynn... if anyone has any suggestions on this front i'd appreciate any info... the cheapest injectors i've seem are £150 each off of ebay so that'll be the last thing i try... no point just changing just one aswell so i'd have to do all four, but i'm hoping it doesn't come to that... another posibility could be the timing is out or chain stretched... i'd check that before the injectors...

does any of that help??? is your ticking always there? even when the car is cold? whats the mileage on urs? any other symptoms???

 

[addy]

Hi ive already been down that road with injector cleaners to no avail what i have been thinking the injectors could have been changed at some time and what ive read through a google search is they have to be re-programmed to the ecu as they could inject at the wrong time which i think in our case to early which could cause the pinking/rattle noise i dont know about you but i hate driving it ive had a 406 peugeot 2.2 hdi coupe for the last three year with no problems and decided i needed a change and im rapidly begining to regret it i could live with the noise if it wasnt so audible inside its like theres a rubber grommet missing in the bulkhead its so clear and like you said once you start listening no matter how much you turn the radio up you can still hear the noise im sure someone else must have had and cured this problem thanks.

 

[addy]

Hi again i missed the bottom of your post its only there when accelerating or on the motorway cruising where i get the unbearable under dashboard noise which as i said earlier i can turn that on or off with the acclerater pedal its louder when cold, but hot or cold put your foot down and between 3000 and 4000 rpm the noise goes its done just short of 110k with full history and goes and drive faultless other than this annoying rattling/pinking/tinkling noise

 

[addy]

Hi did you have any luck with your injector cleaners,im in the processs of removing injectors to have them tested.

 

[Hiffy]

hi... since using the injector cleaner the feels like its running smoother but hasn't got rid of the sound completely... i think it may be slightly quieter now, hard to tell though coz weather and other factors have also changed... i've also noticed that it smokes slightly when i'm accelerating... i can just about make out a small puff of smoke in my nearside mirror on acceleration... i'm gonna try change the fuel filter and then try a stronger fuel additive... i've bought some comma DeTox which is supposed to be a lot stronger than redex or wynn's cleaner... let me know how you get on with your injectors...

 

[addy]

Just to let you all know my pinking/rattlig noise as gone and runs like a dream i removed the injectors and had them tested to find one faulty on number three cylinder so fit one reconditioned injector problem solved.

 

[Hiffy]

Just to let you all know my pinking/rattlig noise as gone and runs like a dream i removed the injectors and had them tested to find one faulty on number three cylinder so fit one reconditioned injector problem solved.

Thats great news... was the sound artually poinking noise then? i'll have to get mine tested too... where did you get them tested? bmw? what was the cost?