i have a 99 tahoe that ran fine, untill i bought a new battery.. now it wont start but it turns over and stumbles.. so far we have checked for fuel preassure but with key on engine off it is in correct range. the spark is orange out of all plug wires and coil wire. we replaced coil,plugs,cap and rotor. and still no blue spark just orange.. not sure if it matters but its not blue. changed battery again still no luck.. PLEASE HELP!!! THANKS

are your battery cables clean? usually if it burns orange is the coil. have you checked or changed 02 sensor,module and you sure you got a good ground comming from moter where it's grounded?

check the wiring harness to body ground next to the battery tray . make sure it's clean & tight.the negative cable should also have a pigtail that connects there.:popcorn: exwldr......

cleaned grounds and ends of cables same thing no start... when you say module is that the ingition module? as far as o2s they are good.

help!!!!

yes on the module and how did you find out the 02 sensor? because if you tryed cleaning them it's awaist of time they may look good but can still be bad. unless you put new one's in..

there should be a ground connection at the thermostat housing on the engine or in that area.look at the fuse box under the hood you'll see fuses that say ignition and ecm.. pull them out for a few minutes and then reinstall.then try to start engine there is also a fuse panel inside the car that will have a fuse that says start or ignition. try the same procedure there. exwldr...

changed module same thing! i sprayed starting fluid in to intake and it fired right up... would you think fuel pump?

changed module same thing! i sprayed starting fluid in to intake and it fired right up... would you think fuel pump?

yes i think fuel pump if it fired up with starting fluid.

sounds like you don't have enough fuel pressure to pop the injectors open. can you hear the fuel pump running when you turn the key to the start position without starting it.?if not check the fuse panel fuse & i believe there is a relay in the under hood electrical panel box.:sunglasse exwldr........