It is a trick to check for consistency ONLY. It does not tell you much. It does not tell you which cylinder unless you rotate the engine to compress at a pre-defined cyl, say #1. It does not tell you compression numbers, if low, how low or how high? The equipment is expensive. The low compression could be due to valve adjustment so there are still a lot of unknowns. Just fire up the engine and do the simple checks.

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Not MBZ nor A/C trained professional but a die-hard DIY and green engineer. Use the info at your own peril. Picked up 2 Infractions because of disagreements. NOW reversed.

W124 Keyless remote, PM for details. http://www.peachparts.com/shopforum/mercedes-used-parts-sale-wanted/334620-fs-w124-chasis-keyless-remote-%2450-shipped.html

1 X 2006 CDI
1 x 87 300SDL
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