One for the experts on vacuum systems!

[ninja_zx11]

Originally Posted by mobilejo

Well I had my engine replaced today and just like you Ninja, I notice a slight improvement but not a huge difference. Vibration is still there particularly at idle, but it's almost all in the steering wheel.

I noticed holdign the steering wheel by the controls (volume and phone buttons) you feel it much worse so now i'm just gonna keep my hands at 2 and 10 o clock - barely feel it there. So yeah, not much of a solution but instead a 'compromise'.

It does seem to be smoother when moving - less vibes at 1200 rpm which is where it was worse before. Still there but less.

During all this, I did go and test a few cars of same age and mileage and they all vibrated the same so I'm ready to give up and accept that maybe this is just the way these cars are...

Thanks for the update.

There is one more thing you can try.Reset the Air mass meter adaptation with ISTA software.I did it last week and it made a difference.Not huge but i could feel.

What happens as the Hot film air mass meter ages,it slowly fails to accurately meter the amount of air entering the engine.And DDE injects less fuel to maintain the ratio and the after effect is engine shiver.I was getting super good fuel economy even much better that the manufacturer's posted ratings before resetting the air mass adaptations.After i did the reset, my economy dropped a little but much better response and i would say less vibration.

With air mass adaptation reset,DDE compensates the difference between the metered air mass and calculated or expected air mass.

One last thing i am waiting is to do transmission mount replacement.Just trying to find tools for that as it requires special puller.

[ard]

Originally Posted by mobilejo

Well I had my engine replaced today

Did you leave out "mounts"??

Originally Posted by mobilejo

During all this, I did go and test a few cars of same age and mileage and they all vibrated the same so I'm ready to give up and accept that maybe this is just the way these cars are...

yeah, then there is that.

[mobilejo]

Originally Posted by ninja_zx11

Thanks for the update.

There is one more thing you can try.Reset the Air mass meter adaptation with ISTA software.I did it last week and it made a difference.Not huge but i could feel.

What happens as the Hot film air mass meter ages,it slowly fails to accurately meter the amount of air entering the engine.And DDE injects less fuel to maintain the ratio and the after effect is engine shiver.I was getting super good fuel economy even much better that the manufacturer's posted ratings before resetting the air mass adaptations.After i did the reset, my economy dropped a little but much better response and i would say less vibration.

With air mass adaptation reset,DDE compensates the difference between the metered air mass and calculated or expected air mass.

One last thing i am waiting is to do transmission mount replacement.Just trying to find tools for that as it requires special puller.

My ISTA cable is on the way so I will reset the MAF settings. I had wondered if that was part of the problem but without splashing out on a new one, I didn't think there was anything I could about it to test it.

[mobilejo]

Originally Posted by ard

Did you leave out "mounts"??

Yes, sorry, no new engine here unfortunately.

[mobilejo]

Ninja - do you have lane departure warning on your car?

I noticed that my vibrations felt alot like the LDWS system going off, but just a little less intense. I decided if I can't do anything about the source of the vibrations, perhaps I could do something about the part it is transmitted to; the steering wheel. Not a fix, but a band aid. At this point I had nothing to lose.

I took off the main s/wheel bolt and put the airbag back in place and started the car. With the wheel loose, i felt much less vibrations, so I removed the wheel completely and cut some 6mm foam numberplate stickers into a ring. I stuck the ring at the location of the red circle here to act as a spacer/damper between the wheel and the hub it sits on (this is not my s/wheel but it illustrates the location):



The stuff I used looked like this after cutting it:



This helped reduce the vibrations by about 30%, which was noticeable, but they were still there.

So next I decided to look at the LDWS motor:



The vibrating body sits on those little black rods, and it's free to move back and forth along those rods - that's how it vibrates when the system is activated; it moves back and forth very quickly. I felt how easily the body moves back and forth by just pressing it with my finger and I figured that perhaps the vibrations that are coming into my s/wheel are being amplified by this. It is after all designed to make the steering wheel vibrate so it's not impossible to think that if the car's natural vibrations are enough to get this thing moving, then I would feel that as increased vibrations.

Not sure either way but it took 3 minutes to remove it and after I did, vibrations reduced to around 20% of what it used to be! A serious improvement - I'm very used to diesels here in the UK as most of our cars are, and now what I'm left with is just 'normal' diesel idle vibrations. I can keep my hands at 3 and 9 o'clock at traffic lights and there is no irritating buzz, just very mild typical engine idling type of sensation.

I can live without LDWS while I have the car, and can refit the motor in 5 minutes when I come to sell it. The airbag on these cars come off soooooooooo much easier than e46 air bags.

On a separate note, I haven't set up my ISTA yet (having some problems getting the cable to recognise the car) but I did clean my MAF with electrical contact cleaner. I must say the car feels more spritely and a little smoother at lower revs such as moving off from a stop. That was a good shout on your part. When I get my ISTA working I will reset the adaptations on the MAF also.

[mobilejo]

Happy thanksgiving to you guys Stateside! I didn't even realise as we don't celebrate it in the UK.

[ninja_zx11]

No i don't have lane departure system but glad your modd made some improvements!!

Can you feel any play in the steering wheel shaft?May be this vibration issue is related with steering mechanism.Something is loose and passing vibrations to the steering.

[mobilejo]

Originally Posted by ninja_zx11

No i don't have lane departure system but glad your modd made some improvements!!

Can you feel any play in the steering wheel shaft?May be this vibration issue is related with steering mechanism.Something is loose and passing vibrations to the steering.

The steering shaft itself seems solid.

I noticed that witht he airbag removed, the wheel doesn't vibrate at all. perhaps its just the weight of the airbag