I have a 97 7.4 vortec with new wires and plugs and cap and rotor but it still turns over quite abit before it starts and when it does it has a little puff of black smoke out of exhaust and runs rough for a second or two any suggestions would be helpfull

i hav the same problem on my 99 sil z71. no codes either. i will let you know if i find out. vice versa.

thanks
james

I find the 97-era Vortec usually has problems with injectors. One solution maybe to try using a higher octane fuel occaisionally, or to use an injector cleaner. Also, in the colder months avoid buying fuel in the morning, as it may contain higher levels of water.