|
Re: 88-98 FAQ's "Is your truck running weird? Check here it could help"
Stumble only at idle yet normal power everywhere else? Black smoke from the exhaust when you stab the throttle after idling for a few seconds? Do the paper on the exhaust pipe trick, if it gets sucked in, most likely an exhaust valve not sealing, could be a burnt valve, stuck open from carbon, or in my case, a bad mechanic lashed the exhaust valve too tight. The low rpm does not allow the cylinder to build enough pressure to ignite the fuel, at higher rpm the increased piston speed moving the air faster builds enough pressure before it can leak out the exhaust valve to ignite the fuel, hence only the stumble at idle.
http://67-72chevytrucks.com/vboard/s...d.php?t=635082
__________________
1979 K10 reg cab short bed 33x12.50s - GONE
1988 4x4 reg cab long bed 337k miles - GONE
1995 Z71 GU6 G80 F44 ext cab short bed 149k 305/70/16s - GONE
1995 NZZ GT4 2dr Tahoe 3" lift 14 bolt sf 155k 305/70/16s - GONE
1994 Z28 M6
1995 Z71 GT4 G80 ext cab short bed 215k GONE
1997 GT4 G80 Yukon 4 door leather, sunroof 168k miles GONE
2003 Avalanche Z71 GT4 G80 165k miles
|