'92 chevy lumina van running rough after fuel pump replacement

SOURCE: car runs rough at idle

clean out ur throttle body, just follow the hose from the air filter to the throttle body. Need 2 people to do this. Don't remove the hose completely from the throttle body. Just enuff to be able to spray ur intake cleaner into the throttle body. Do this especially if its worse when the motor is hot, as this would confirm the problem.

SOURCE: Service Engine Soon Light and Rough Idle (Below 1200 rpms)

do you get check engine codes?..have you done a leak down test and compression test to determine mechanical engine health?

SOURCE: 1999 pontiac grand prix . will not run

If wiggling the wires cured the code, then one of the wires is broken inside the insulation. Pull on each wire one at a time. look for the colored insulation to stretch, this will be the broken wire. For the other car that wont rev up, this is a common when the catalytic concverter is plugged up. This will also cause MAF codes, and in turn, TRAC OFF light.
See http://www.greatautohelp.com

SOURCE: 2001 Chevy Astro Van

Needs Crank sensor. Good luck

SOURCE: 1996 s10 2.2 engine starts but idles rough and will not rev up.

Hi! You must be frustrated by now! your code is marking that the O2 sensor is bad in bank 1. Did you replace the O2 sensor that is located  before the catalytic converter?  The S10 has an O2 sensor specially made for that cat. its about 30$ That would explain for your blackened spark plugs; your pc on the car is asking for more fuel. GOOD LUCK!!