Help Please... engine rumble when idle???

[Ash187]

Hi guys,

i have a 2005 Audi A3 2.0 TDI 6 speed manual...

when the car is driving it is absolutly fine, no problems when accelerating.
but when its idle for instance at traffic lights the car will rumble and it comes from the engine. i have opened the bonnet and you can see the whole engine shaking... can anyone help me out in what it could be?

thanks
Ash

 

[tdisportuk]

hi ash,



by the sounds of it. it could be the engine mounts? does the ride seem more 'bouncy' at all?

 

[rickyquicky]

Ive got a similar problem...

Sometimes when the cars is idling you can feel a 'wobble' through the car coming from the engine. It also happens sometimes when im driving at low revs sometimes. Its not making a noise though.

Full throttle/acceleration/decelerating etc its fine.

Dual mass flywheel has been suggested to me already which looks likely, but could be an engine mount, or even intermittent misfire (blocked injector etc)

 

[robby]

From what i've read on here to check if it's the DMF try this
when in neutral and the car is shaking dip the clutch, if the shaking stops it's probably the DMF

 

[rickyquicky]

From what i've read on here to check if it's the DMF try this
when in neutral and the car is shaking dip the clutch, if the shaking stops it's probably the DMF

Cheers...do you have a link to that thread/info?

How would that work in a DSG then? In 'P' would that be equivalent to dipping the clutch in a manual?

 

[tdisportuk]

@rickyquicky - ive got that issue! happens sometimes gives a slight wobble, but when moving its fine. also noticed you can feel it more when going uphill.

was told it was an injector loom?!! but wouldnt that make it worse off than just a slight wobble here and there?!

 

[Ash187]

yeah it feels worse on the uphill during standstill...
I'm thinking it might actually be the engine mount... but i have no real idea...
has anyone had this kind of thing that has had it fixed? or is there anyone i can take it to get it looked at in the South-East London/North Kent area?

Ash

 

[cooltempo]

I had this problem, it was pretty bad and i certainly noticed it more when on a slope. It appeared for me after a stage 2 remap and i noticed the car was idling at a slightly lower rpm. I called the guys at PDtuning and after a bit of research they found that Audi actually updated their software to allow 2.0 tdi's to run at a slightly higher rpm... it was originally low to attain low emissions figures. ... so looks like the remap had cleared this and i had reverted to the lower idle rpm and this resulted in wobble / judder.

They went into VAGCOM and raised the rpm to Audi's recommended optimum, which is around 970rpm if my memory serves me. Anyways it solved the issue for me. its much smoother now.

Of course this might not be the solution for everyone (or anyone but it worked for me. When i looked into it I found it could of been several other things. Engine mounts, DMF, DPF (if you have one), injector loom or dirty / blocked EGR. Luckily the most straight forward fixed worked for me.

Hope this helps some of you having this issue!

Mo

 

[tdisportuk]

hmm, im sure that would definatly not be the case for me. The car has never been remapped (well not to my knowledge, pretty sure the previous owner has not mapped it!)

is the injector loom a major job? would just be nice to get these little things fixed whilst i can rather than it getting worse off in the future..

 

[cooltempo]

mine wasn't mapped either, (previous to my stage 2) i think it had just been updated during a service or some work at Audi at some point, enabling the higher rpms, my remap actually lowered it and brought in the judder, engine was shaking too. It's worth looking into as there maybe nothing to fix....

but like I said could be something else. just good to rule these things out. its a bit of a tricky one as there are so many possible causes.

 

[Ash187]

I have heard that a ECU flash might fix it, but i have no idea where to get one done... (I'm new to Audi's )

 

[cooltempo]

Well I guess you could try talking to your local Audi dealer or this could be sorted during a remap process at a decent tuning place.

 

[rickyquicky]

@rickyquicky - ive got that issue! happens sometimes gives a slight wobble, but when moving its fine. also noticed you can feel it more when going uphill.

was told it was an injector loom?!! but wouldnt that make it worse off than just a slight wobble here and there?!

Injector loom would make it misfire which would take the engine out of balance, and if its very intermittent there might not be any real loss of power so it might be possible. Rather injector loom than DMF!

Not noticed the uphill thing, will look out for it next time see if that makes it worse.

Mine doesnt just happen at idle, it shakes at low revs sometimes as well.

 

[Ash187]

well have tested some more, it only rumbles/Vibrates the car when its idle... i can put it into 1st gear and go to biting point and the rumble stops.
It feels worse when uphill but still happens if I'm stopped on a down hill. just pushing the clutch down on its own does nothing for the rumble, it carries on just as before.
the car drives solid and has no issue on low revs. its only when stopped in traffic that it does this.
I have noticed it takes a few minutes for it to start doing it when i first switch the engine on but inevitably it will happen.

Can anyone think what it could be as its making me go nuts, and its really uncomfortable when in the car.

 

[cooltempo]

Honestly this is exactly the symptoms I had before I had my idle rpm raised. ... here's a quick test, if you give it the smallest amount of gas you can when idle (in neutral) so you bring your revs up only a tiny amount to around 900rpm or just above, does it stop shaking / vibrating? if so then you need to get to someone who has vagcom and the know how to change your idle rpm.

Mo

 

[Scott]

mine has done this slightly since new, 09 CR engine, not sure if it's as bad as you describe though? only happens when engine is cold too

 

[Ash187]

Honestly this is exactly the symptoms I had before I had my idle rpm raised. ... here's a quick test, if you give it the smallest amount of gas you can when idle (in neutral) so you bring your revs up only a tiny amount to around 900rpm or just above, does it stop shaking / vibrating? if so then you need to get to someone who has vagcom and the know how to change your idle rpm.

Mo

i will try and see if i can get this sorted with the VCDS... i am thinking of buying the VCDS myself so i can do the work without travelling... I think i would be good at it as im an IT head as it is...

now to find someone close to me to check it over for me...

 

[Ash187]

Latest update... Still not had the chance to check the car with Vag-com but I have noticed that if i drive with the Air con on (E-Con switch off) the rumble is not that bad. but if i switch on the E-con the car starts to rumble/vibrate quiet badly. can anyone think what this could be? why the car would be affected more when the AC is off?

thanks

 

[rickyquicky]

itwasntme187... the air con pump runs off the engine, if its on you are increasing the load on your engine as it has to drive the air con pump too.

That might mean you have a fuelling issue as your ecu will chuck in an extra tiny bit of fuel to keep idle steady whilst it runs the air con pump, therefore helping any issues you might have like underfuelling (due to faulty injector/fuel pump etc). Another reason could just be that the load on the engine is masking the fault slightly as the revs drop a little and the shaking isnt so obvious.

An update from myself... had a diagnostics done on my car - intermittent misfire on cylinder 3 is whats making my car shake, not the flywheel so really relieved about that!!! Most likely an injector so just got to narrow it down now!

 

[rickyquicky]

Just noticed youve got a tdi mate, id suggest having a diagnostics done as yours sounds like a misfire too.

Where you from south-east london/north west kent? My mate will do a diag for you cheap if you want he's based in bexley...

 

[Ash187]

Just noticed youve got a tdi mate, id suggest having a diagnostics done as yours sounds like a misfire too.

Where you from south-east london/north west kent? My mate will do a diag for you cheap if you want he's based in bexley...

hey thats not far from me at all, i live just near to Dartford, and I work in East Dulwich. That would be great if your mate could sort me out. could meet up after work sometime