Based on this graphical data from the VW it seems that it is more than likely the cat has a serious restriction?

http://imgur.com/a/ttQE2

As a memoir,

1 bar = 14.5038 PSi x number of bars is PSI, if it is required to change bar to psi then number of bars pressure divided by 14.5038 = PSI

Thank you for your advice. The engine has been rebuilt and is now exceptionally clean, the breathing problem through the inlet manifold and cylinder head eliminated. The cylinder compression's were uneven before the engine was rebuilt as I remember, the built up of compression's were also slow. I di...

Thanks Mickey, Very much appreciated for your time and valued advice. I had looked at measuring blocks 013, I must confess that I didn't like what I was reading. The values were - 1.91 mg/str, - 1.81 mg/str, 2.99 mg/str and - 1.69 mg/str. The reading 2.99 mg/str caused me to look back at the data I ...

Van is what appears to be under powered when driven, not sure at the moment if the cat is seriously restricted causing high back pressure. The van starts OK and engine runs OK, free revs to governed speed OK. VCDS pulls back no codes based on an auto scan. I did collect some data using Snap On equip...

Welcome new members, hope you enjoy your time here on the forum, some great members on board.

Edit spelling

I know a man who knows the answer to this problem, and as soon as he tells me I'll pass on the information.

I wonder if it is something to do with comparing analogue and digital signals

Welcome Hash Cash

The gauge kit can test pressure up to 15 bar.