hey, i just took my 92 blazer in for a emissions test and it failed the Hydro Carbon test, the limit is 57ppm and i had 103ppm. before my test i changed plugs, wires, distuator cap and coil. i have still noticed a little hesitation while acclerating. could this be bad timming if so how would i correct this? any ideas?

did you replace the rotor?

Did you clean and reinstall the EGR valve?

Did you check the timing with the timing wire unattached?