1.9 tdi Vibration on Takeoff

[Isitme]

Hello,

 

While taking off from stand still the car will will vibrate like it was on high load, same as if you put in too high gear and too low revs. If i accelerate by giving more throttle then the vibration is minimized.

 

I understand that this should be somewhat normal, but my friends octy has a very similar setup and it pulls a lot better while taking off which is why i am trying to locate the problem.

On higher revs the car feels smooth and pulls very well, but on lower revs it feels like it has not enough power.

 

This couldn't be the flywheel since there are some mornings with rich air where the car will pull like new without any shaking.

 

Has anyone experienced similar issues and managed to fix it?

 

So far i suspect that it could be some of the below issues:

 

1. MAF sensor, because unplugging it doesn't seem to make much difference, but the vibration seems to get a little worse (Maybe it is slowly on its way out?).

2. CCV breather not operating because i get oil blow by from oil filler cap. Maybe the additional air from CCV going into air intake changes the air/fuel ratio or Too much pressure in crankcase?

3. Vacuum leak, which i understand can increase pressure in engine from vacuum pump? Because when removing the oil cap i can feel pressure coming out of it, but it does not look like exhaust gasses from piston ring blow by. No smell or smoke coming out just pressurized air.

4. Related to vacuum leak i have also received some over boost error codes. It happened much more often, but Mr.Muscle helped to solve it. Now it happens very rarely. Maybe the vacuum is too weak to move the VNT?

5. Or maybe the catalytic converter is clogged up and is building too much back pressure for the engine from exhaust side?

 

Car is Octavia 1Z 2007 1.9 TDI (BXE) with 155K miles on it .

 

I will appreciate any input or comment on the topic. Thank you!

 

 

[Guest]

My experiences would point to a fouled clutch friction plate.

 

This happens more so if car had been sitting a couple of days or weather is damp.

 

A couple of race starts to burn oil/dampness out and all is well again.

 

Just saying...

[Isitme]

58 minutes ago, MicMac said:

My experiences would point to a fouled clutch friction plate.

 

This happens more so if car had been sitting a couple of days or weather is damp.

 

A couple of race starts to burn oil/dampness out and all is well again.

 

Just saying...

That doesn't really explain why sometimes on morning time it works perfectly. You can feel when the car has power to pull. That seems to be completely different from vibrations from clutch. 

I understand it can be clutch, but the clutch feels fine and i'm trying to rule out cheaper "lets try to change it and then see if it worked" options. 

Edited 21 February, 2018 by Isitme
typo

[Guest]

Could be the turbo is so coked up it isn't returning reliably to the low speed setting.

 

A good clean may help.

[Isitme]

1 hour ago, MicMac said:

Could be the turbo is so coked up it isn't returning reliably to the low speed setting.

 

A good clean may help.

I have cleaned it before, but maybe it didn't get cleaned entirely. Does anyone know when the turbo is at low speed setting? Is it at full vacuum or is it when there is no vacuum?

Basically what i want to know is when the vanes of the turbo are most closed.

Because when i cleaned the turbo when i sucked the vacuum i felt the vanes jump over one obstacle harder. Maybe it is sticking at that place to close the vanes.

[Guest]

Disconnect the vacuum feed to the turbo and it will be stuck in the slow speed setting.

 

The actuator should move smoothly by hand along the full length of its travel.

[Isitme]

On 2/22/2018 at 00:10, MicMac said:

Disconnect the vacuum feed to the turbo and it will be stuck in the slow speed setting.

 

The actuator should move smoothly by hand along the full length of its travel.

Is it safe to drive without that vacuum line connected? For the sake of testing it? Or will it cause overboost?

[Guest]

I think it will be the opposite.

[Isitme]

1 hour ago, MicMac said:

I think it will be the opposite.

My understanding is that at low speed setting the vanes are closed, so the minimum exhaust gasses can spin the turbine faster by generating more boost. When you start to drive faster, the turbine will spin faster, but vanes will still be closed, so you will get the over boost. 

 

That is just my assumption. I have no clue if that is actually true. So i wounder if sucking vacuum will open or close the vanes?

[Guest]

Stop typing and get the spanners out!

[Isitme]

10 minutes ago, MicMac said:

Stop typing and get the spanners out!

Thanks for the encouragement, but i'm scared as **** to remove the turbo, but i will try to find courage to do it sooner than later. BTW today is -20C here so i am not going outside