compression numbers and dollar bill test

[RadioRental]

My van is sucking in dollar bills all over the place but one noticeable area is the tailpipe. Not so much sucking right in but flaps the bill back fairly rapidly. Recent tune up parts (o2 & temp2 sensors) have cleared up some rich idle issues and the dollar bill flapping is very much less aggressive.

So, me not knowing much about anything I guessed I might have a valve issue on one of the cylinders. I just did a compression test and got these numbers; 125, 137, 127, 150 ( I did forget to disable the fuel pump before doing this, another blond moment, but that leads to poorer results I think)

So, reading through other's posts I seem to have decent numbers, everything is within a 10% deviation of the mean.

Is there little correlation between the compression results, out of spec exhaust valve clearances and the dollar bill test?

many thanks! /pauric
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'87 2.1. 125K 4spd Not rebuilt "Red Dwarf"

[MarkWard]

I have to say in all my years as a VW/ASE Master Tech, I don't recall ever using a dollar bill for testing anything. Maybe the closest was setting the points with a match book cover. If the injectors are spraying during the compression test, it will wash the rings and have an impact on the compression readings. Drive the van and do a proper compression test on a warm engine. A cylinder leak down test can be more accurate than a compression test. Regards,
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[RadioRental]