A friend of mine was an engineer for Shell oil and they had Chevy send over some new Vega engines for testing.He said they were so bad out of the crate he sent them back and said "NO Thanks".
Chevy finally wised up,probably after spending $Millions on warranty repaires and started using iron block engines.They turned into decent little cars finally.
That, and the RUST. Few cars before or since rusted as easily and thoroughly as the Vega.