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Hi guys,

While I'm changing the oil this weekend, I'd like to baseline my cylinder compression readings so I have them to compare against down the road.

To make the measurement I need to pull the fuse for the fuel pump and the ignition, and I'd like to make sure I'm pulling the right ones.

For the fuel pumps it looks pretty straightforward and pulling fuse B3 and B4 should do the trick (primary and secondary fuel pump fuses).

For the ignition it looks like htere are 3 fuses in play (B5, B6, and B7) and it's not immediately obvious which (or all) is the right thing to pull. What's the verdict?

Knut
 

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B5 provides power to the coils, that should keep the sparks from flying. If you haven't pulled the plug wires before, you need to make a tool from heavy wire (OXY welding rod works good) it's a loop to reach down in the head and grab the plug wire below the boot. Otherwise you risk pulling the wire loose from the boot end. I've seen a commerical one from Snap On.
 

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Ditto on above and with a warm engine and dry cylinders.

To make an even more in depth comparison, check them wet (a little oil in each cylinder) and keep those numbers also.
 

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pull all the plugs - press the accelerator all the way to the floor (butterfly open)
yes...make sure the throttle is wide open when performing a compression check. I've seen many people forget to leave the throttle open. it'll skew your readings.
 
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