:confused: :confused: my 99 suburban has a random misfire issue. has the vortec 350 with 130k miles on it. i just bought the truck a couple weeks ago and this problem has happened a few times. i never feel the mis or the truck doesnt seem to stumble, but the ses light comes on. the previous owner said this truck has done this for along time. he said he replaced the cap, rotor, plugs and wires about 15000 miles ago and this didnt seem to stop the problem. i have a friend that has a tahoe and has the same problem. is this common, if so what usually is the cause? i have switched to mid grade gas about 800 miles ago and have not seen the ses light come back on, im stumped. Timing? computer? a sensor? any help would be appreciated.

Look at some of my other posts in this forum, as I don't feel like re-typing it all again. I would say timing or knock sensor issues.

thanks for the reply, i done some searching and have a few ideas. seems like sticky valve could pssibly be the problem also.