2003 Nissan Altima Repair Question
Nissan Altima Engine Problem
You could have intake or exhaust blockage. someti mes the catalytic converter wil fail internally and fall in on itself clogging the exhaust and the Altima has like 6 converters. The ones nearest the engine are most likely to fail.
To go over more possiblities I am giving you a diagnostic walk through. Just use the link below to get to it;
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