Question about 1993 Chevrolet Suburban

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Would not pass emissions test. Code suggest too lean or rich.

The service engine soon light comes on after vehicle runs for 20 mins or so and warms up. It will go off, then come back on. I have installed a cyclone in the air intake to improve mileage.

A code check at the Chevy dealer revealed a lean code. I am running several tanks of Lucas top head lubricant and fuel injector cleaner.

Like others have mentioned here, I get a rough engine every once in awhile and then it will go away.

Anything else I should consider doing besides what I have mentioned?

Thanks again for being kind enough to respond to my question.

Joel Hendelman

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A lean code can be caused by a vacuum leak check all hoses and intake for leak

Posted on Nov 14, 2008

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