Happy New Year.
If you skip back to page 539 in this post you will see the image of the Liquid Moly Diesel purge.
Some people just run their fuel tanks low and add it then but you can do what I did yesterday and use it neat. Not done it on the A2 yet though.
The 1.9 TDI in the A4 is a PD engine but if you look up on YouTube it shows the diesel purge being used on both PD and non PD (Pump Diesel) engines.
The idea is to have a loop with the filter in it and run it for approx 20 through the rev range.
I also cleaned the MAS (mass air flow sensor) while changing the air filter. Running sweet as.
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