I have a 1995 chevy 1/2 ton 350 . just isn't running right, sometimes idles rough, got to feather throttle to take off .no power seems like nothing there in the midrange, wants to die at idle , hesitates and bucks on acceleration. I have rebuilt throttle body put in throttle position sensor , idle control sensor tested map ,new exhaust and o2 sensor ,plugs cap rotor .run a vacuum test fluctuates rapidly between 15 and 18 , also sprayed around intake for v leaks . pulled each plug wire with running seemed like they were all hitting but when I did pull the plug wire off dist cap it makes the coil wire arc to the coil/ does it on every one i don't no if this is normal or not. thanks also have replaced fuel filter
05-24-2012 07:26 PM
Sounds like a weak fuel pump. Perform a fuel pressure test.
vortec engines like about 62 PSI while running at Idle.Just a few pounds lower than spec can result in poor driveability.
05-25-2012 09:46 AM
1995 chevy throttle body--9-13 psi
05-25-2012 06:45 PM
Originally Posted by 1932bantam
run a vacuum test fluctuates rapidly between 15 and 18
Sounds like time to do a compression test. ;), then check for broken valve springs.