engine dont have powr at 4000 rpm
 

need help for this.
my engine lack powr at 4000 rpm
, run well 1 to 4 rpm
my engine dont have this problem before

carb or FI

ok. thx
s4 na
fresh injector rebuilt
not easy to déterminate what is wrong when u arent beside the car but
any help and thing to check, will be apreciate

maybe the solenoid, make sure all the wires for the spark plugs and everything is plugged in.

check your coils and all grounds. good luck!

If the car hits a "brick wall" at 4000 RPM (3800 RPM to be specific), it means the secondary injectors are not firing. At 3800 RPM, the ECU switches from ~80% duty cycle on the primaries to ~40% on the primaries & ~40% on the secondaries. If the secondary injectors aren't coming online, the engine will not rev past 3800 RPM.

-=Russ=-

nice
big help there