how does keys with chip work? sometimes it will start sometimes it wont.it may run for a while and then stop and not restart. coil pack and module has been changed crank&cam sensor has been changed also fuel pump can you help
Most of the key chips work or do not, not intermitantly. Is it a 302cu.in(5.3 litre)? They are famous for rounding off the camshaft lobes which could lead to the problems you describe. Including stalling after the pressure in the hydraulic lifters build up. 350's will also have this problem.
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