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Q: with the#1 piston up were should the rotor button be pointing

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If I have the #1 piston up were should the rotor button be pointing when I pull the distributor cap off.
My car has an automatic transmission.

A: The rotor button should be pointing to the ...

The rotor button should be pointing to the number 1 position on the distributor cap when the number 1 piston is at top dead center (on the compression stroke). The pistons come up two times during the combustion cycle. Once for the exhaust stroke and again on the compression stroke. The mechanical ignition timing should be set so that the rotor hits the corresponding cylinder on the compression stroke to ignite the air/fuel mixture.

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