I can't figure out what is wrong w/my Z. Its a 94 Z-28 M6. I had a fuel pump go out and thought it wuz the opti so i bought a new MSD Billet Opti, MSD GM Blaster coil, MSD 8.5 super conductors, and NGK TR55 plugs. We got all that put on and it wouldn't start so i knew i had to be the Fuel pump. I installed a Walbro 255LPH and it fired out after awhile of turning over. I figured that the excess turning over wuz due to a fuel shortage at the motor. Well i got to noticeing that when i stop sumwhere and kill it, it takes forever to start back and sumtime the starter grabs the flywheel when its tryn to crank. Also when driving i have to ride the clutch to keep it from dying. and 5&6 if im tryn to cruise the shifter shakes L-R really hard. I can't hit 6th till about 65 MPH other wise it get to shaking sevearly. I drove halfway across Tx and when i got 2 the place i wuz goin i popped the hood and put water on the headers to see what cylinders were cool. 1,2,7,8 were nice and hott. 3.4.5.6 were not very hot, it took alot long for water to burn off. I took it to the track just to see what it would do. Launched at 2500 chirped twice bogged down to 1500ish and wuz extreamly sluggish up to 3000 then went good to 4500 the started trying to bang out. The thing that has me puzzled is in the mornings when its sat all nite i can go out and it pops right off and runs AWESOME for about 10-15 min.


Does anyone have any advice on what to do or has had this problem be4????



Thanks,
Steven

 

First thing I would check is plug wires. Make sure each one is going to the correct plug. If that doesn't fix it I would check to see if the opti is installed correctly. It is posible that the splines on the opti shaft aren't lined up correctly. What is your fuel pressure now? Did you change the fuel filter as well?

 

yes we did put on a new fuel filter. when we installed the opti we put it on with the rotor in the same position as when it wuz taken off. not sure of fuel pressure. do u think i could have to much?

 

Too much is not likely. I am running a 255 with my LT1 and it runs fine. Check the pressure to make sure. You could have problems elsewhere. While checking the pressure remove the vacuum line and watch the guage. It should rise some. This will tell you if the regulator is working. You may have a faulty injector or regulator if you have made sure your ignition system is installed properly.

 

I will try that out. i wuz thinkn the injectors could be messed up and im lookin for a set of 30# injectors right now.