Failed smog test

[quote:b08f0b53e9="sybercage"]I have a 1996 Grand Prix SE, 3.1 liter with 150,000 on it. The other day it failed inspection with the codes p0303 ( misfire cylnder #3 ) and p0404 EGR flow problem. I`ve fixed the misfire and replaced the EGR vavle but today after driving around for about 12 miles the light came back on. The light came on after I got on the gas hard so I`m guessing the EGR valve wasn`t bad. What else goes with that part that could cause that code? I rest the code by removing the battery power, will that reset the code or must I take the car in and put on a scanner? Any help would be great, I have 5 days till it has to be reinspected.[/quote:b08f0b53e9]

The light came on after I got on the gas hard. You need to get scanned again maybe its not the same code/s

How did you fixed the misfire on P0303?

An EGR can do a lot of tricky stuffs.

I replaced every spark plug, wire and the caps. I also replaced the lifters. #3 was collapsed so I did them all.

[quote:5440222c2f="sybercage"]I replaced every spark plug, wire and the caps. I also replaced the lifters. #3 was collapsed so I did them all.[/quote:5440222c2f] Which lifter the int or exh