Flat spot?

[6pak]

Hello again and after finding a truck load of air leaks and blocked injectors the 280z finally runs. A local garage helped out making sure it's running but it feels like its running flat, it does run but I feel like i need to put my foot to the floor to get any where. Idles fine and I checked plugs and they look perfect. Also seems to really struggle from 4000rpm onward like it's just running out of power. Not to sure where to start. New fuel pump,regulator, injectors cleaned. Any input would help. I feel like I'm close. Thanks

[siteunseen]

Timing?

[SteveJ]

Go through the diagnostics in the fuel injection reference manual: XenonS130 - S130 Reference

[83.FairLadyZX.Bullet]

sounds like your timing is just a little bit out. like just a hair. not much but enough to screw with it. also maybe check your trans fluid and filter? maybe it needs serviced... or the air flow meter, fuel pressure regulator, cold start injector, etc.... may not be exactly in the fuel rail or lines.... maybe need to clean the tank out... there are many many things it could be. ran into about the same problem on my hubbs' supra, the previous owner had tried to wire up a different ecu, and in doing that, he crossed 2 wires, they were the same color so he thought they were the right places i guess... fixed that, she ran like a charm.