i discovered my 1990 acura integra ls has a 1991 motor in it will i b able to pass emissions test

California? You may have to go to CHP Referee. They settle those kinds of things, and will probably pass it if tail-pipe emissions pass and CEL works, and no obvious tampering like cold air intake or headers

Depending on where you are you should be able to. In New Jersey, for example, pre-1996 models are subject to a tailpipe emissions test. They put an emissions analyzer up the tailpipe and test the exhaust that's coming out. As long as what's coming out meets or beats the car's model year specifications (in your case 1990), the check engine light works, and the catalytic converter has not been removed (1974 and newer models) you're good to go. California is, I'm sure, a whole different ball game. Be sure to go through after the engine is fully warned up to operating temp. What did you fail for? CO2? HC? NOX? HTH. -Jim

thank you very much im in ca. how do i see the referee what steps to get there

http://www.performanceforum.com/wesvann/honda/cert/cert.html

http://www.asktheref.org/?gclid=CJaDwLbJzsQCFQyEaQodmAYAFg

The last one is most important

thank u so much

Hope it passes, good luck and very welcome