try changing the cap and rotor
multiple random misfire on 4.3 vortec why?
burnt valve...
If your 1997 GMC 5.7L Vortec has a misfire at an idle but not while under throttle, the problem is likely the timing. This can be adjusted.
NO. That would be the TBI / throttle body injection engine Not a vortec. The vortec will not work in the 91.
Vortec 6.0L
The 2001 model of the Light-Duty Silverado 1500, had an option of four engine sizes; a 6.0L Vortec V8 engine, a 4.3L Vortec V6, a 4.8L Vortec V8 or a 5.3L Vortec V8. The Heavy-Duty 1500HD comes with three engine options, these are 6.0L Vortec V8, 8.1L Vortec V8 and a 6.6L Duramax V8
P0300 = random misfire.
5.7 vortec
315 hp
Vortec V-6
it is an 8 cylinder
As far as a direct bolt in NO. But if you have the smarts and the know how, you can put anything in there.