what is the difference between an older 2.2 liter and the 2.2 ecotec?
Everything except for the fact that both are inline 4 cylinder gasoline engines with a displacement around 2.2L. Do a couple searches, I know this has been posted before.
the Eco is Dual Over Head Cam
the 2.2 is a Over Head Valve engine. the cam is in the middle of the block on that one

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