could be off timing, it could even be the fuel injection system, there is alot of things that could be wrong with it... to me it sounds mis-timed, but that's just my best guess. did you change any belts or even take any off, yourself right around the time you noticed this problem start? or mess with the distrubtor/spark plugs/spark plug wires? did you change the spark plugs recently? if so were they properly gapped? anyone that could tell you what's wrong would need a bit more information then what you've provided.

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slipknotpsycho Reviewed by slipknotpsycho on . car experts, help me out...my car is shaking i drive a 2000 nissan maxima SE automatic. lately when between 600 (idle) and 1200 rpm my car starts shaking/chugging/hesitating...whether in gear or in neutral. when it gets above about 2200 rpm the chugging goes away. the chugging is at its worst when i'm in 4th gear travelling around 37-40 mph and at 1300 rpm or so. when i turn on the a/c it gets worse...the chugging gets stronger and slower. when i turn off the a/c it gets weaker but chugs more rapidly. my car has lost a lot of power Rating: 5