I was driving my suburban this evening and when I got on the highway every thing was fine until I hit 70 mph .Then it kind hesitated for a min are two and the SIL came on.went to AutoZone pull the code and there was 2 codes and both was p0304 cylinder 4 misfire.
Some other strange things has happened not to long ago in short , it cut off on me doing about 35 mph ,and wife said it was hard to start for her a few days ago.I plan on changing out the fuel filter this week end,
It's a 99 k1500 suburban with about 111000 miles on it.I put new plugs in it around 90,000 and a new fuel filter at the same time. I plan on replaceing the wires?as far as I know there still factory. Out side of that I'm lost.
What else could thhis be?