My friend @ work has a cavalier and it hesitates really back
and ill sit at a light and its start revvin and almost stall, to the point where everything flickers

The check engine light does come on also
any suggestions?
anyone got a list of engine codes for a cavalier
btw its a 1999

 

make sure theres no huge oil leaks, has the battery or any big work been done to the motor?? could be hunting idle... plugs/wires.... needs to be cleaned out... get it scaned.

 

maybe the altinator, Ive replaced 2 and had the same symptoms as your buddy :P
mind you that was in my '90

However, the earlier cav's were more notorious for those problems than the 3rd gens (I have a 98 Z24)

 

umm check the code if the check engine light is coming on

 

If it was just the engine light i'd tell him to check the gas cap. Make sure is on all the way.