Hi All,

Long time lurker first time poster and would love to get some advice on an issue im having.

Due to reasons i had my EGR and DPF "deleted" (car switched off while driving with no error codes, dangerous to say the least). EGR and DPF were mapped out and car slightly tuned for performance and economy, results were awesome.

With that done a few days ago i noticed a deep sound when starting the car but only at idle. I assume it is a small hole in the exhaust or a dodgy seal when they put the exhaust back on (to be taken back to them). I did have my brother rev while i listened and it deep sound deeper with a slight gurgle.

As i have access to VCDS i started to play around, no error codes and did the block 11 test i graphed and logged the results. The car is severely under boosting from actual compared to specified with control duty cycle sat at 100% on idle and then dropping as i floor the car. Please see results here:



Red: specified, green: actual, yellow, duty cycle. 900 to 2500 at top for graph.

I then found my self a long road parked up and went into basic settings and just looked at the charge pressure cycle which flashed the coil light and heard it being activated. I did not run the basic setting just in case i screw something up.

I then put my foot down and it seemed somewhat more responsive i did log this which i will add after work. I then did another run and graphed it:


green: specified, yellow: actual, red: revs, grey: duty cycle. 900 to 2500 at top for graph.

When it comes to turbos im a complete beginner but with the deeper sound i suspect something is going on but would my potential exhaust leaking cause this? Isit something else like an actuator, tired turbo etc.

Any direction/ help would be appreciated and please dont slam me for the 'delete'.