Engine

Compression Check Tip

When doing compression checks, you should always ground the secondary coil outputs for
two reasons.
1. because without the load of the spark plugs the voltages go much higher and can cause
damage to the ignition module, and
2. because the other 7 cylinders are pumping through the spark plug holes any raw fuel they
can find. Sparks are not a good idea. Lit an engine on fire this way in my youth, it makes your
heart go pretty fast finding the fire extinguisher!

Mark