*** FSI Erratic Running Possible Solution ***

Topsie

Member
I'll start this by saying I should of taken pictures and that this may not solve FSI issues for everyone.

So, i started noticing a strange clicking noise coming from under the bonnet when I turned on my ignition, I assumed this was normal, one of the solenoid etc. however the clicking progressively got worse. This was accompanied by the normal poor running, surging, misfires etc that a few get from their FSI's.

I investigated the noise and found it was coming from my throttle body, I went into VCDS group 60 and found ADP O.K, I switched to basic settings and the the output once again was OK, i tried again, however this time i got an error. I was getting about a 70% OK to 30% error rate when setting the throttle body so thought I would investigate a little further.

I removed the throttle body to clean and turned the ignition on with the throttle body so I could see, to my surprise the throttle body was twitching, when pressure was applied to the flap the throttle body would kick and click quite loudly. I assumed it was beyond economical repair and decided to replace.

Because I'm a curious type, I removed the retaining clips from the black plastic cover to reveal the electronic wizardry inside. Inside is a motor, a drive wheel and a connecting cog. On the drive wheel are a number of brushes, a bit like a scalectrix and on the back plate are the corresponding tracks. I'm going to assume this is the potentiometer or feedback loop.

These tracks were soiled in carbon from the motor and it doesn't take an electrical engineer to figure out that this was crossing the tracks for the feedback and really messing things up. I cleaned the tracks with some contact cleaner, reassembled, connected to the car and applied pressure to the flap in the same manner as before with no kicking or clicking (the flap just firmly remained in place) carried out calibration and took the car for test drive. The car drove like a dream, no hesitation, no jerkiness no obvious misfiring. I was amazed.

Obviously carry this out at your own risk, be cautious of the brushes, they are very fragile (i bent one right back just brushing my hand against it by accident) but it really has made a massive difference to my A2, I believe the throttle body was essentially moving all over the place instead of staying in one position or the indicated position was very different to the actual position which was throwing the whole engine management air/fuel all over the place. This may of just been a very specific problem to only my car but all these throttle bodies have motors which produce carbon which has to go somewhere!

Nick.
 
Back
Top