My ninja is losing power when i get into it. Idles great on all 4 but when i get going it loses power and seems to be just running on 3 cylinders. I have change spark plugs and wires and that didnt help. The plugs are also producing a weak spark. Not sure what would cause me to lose power when i get into it. At a loss from loss of power

Check EGR valve to make sure their isn't a piece of carbon stuck under valve seat. Also you need to check exhaust back pressure to make sure you don't have a converter pluged.

You need a dealer, there is a real problem going on here, way over the head of any home do it yourselfer. The main reason is the special tools required to interface with the control modules that are throwing these codes

run fault codes and look for MAP/MAF sensor and accelerator position sensor problems

why would you have the brakes checked if your engine is running poorly. the engine while running makes vacuum and if that is not running correctly it will effect other systems. brakes for one work of a vacuum booster. so no vacuum sure the brake pedal will be hard to work. you will want to pull the plugs and test the compression of all the cylinders and write them down and compare that numbers first. my guess you have some bad valve issue or what they call blow bye and losing compression on 1 or more pistons. which may need to remove the heads and rebuild or replace. or even replace the engine all together depending on whats wrong. start with a compression test and go from there.

Check your coil, check the cap and rotor for wear have the battery checked for low voltage or a dead cell and have the alternator checked.

It sounds like you might have a clogged catalatic converter on the exhaust system.

maybe coil pac!!!

Check the rear wheel cylinders if you have drum brakes on the rear. Check the master cylinder cap to be sure it's on right & snug. Use D.O.T. 3 fluid,not synthetic. If you're losing fluid there's a reason. Check the front brake pads & slides for the calipers,could be frozen with rust & eating up the pads. Fluid would seem low if the pads are shot.

tune up or catalic convertor stuff uped

sounds like an ECU fault.one of the chips is breaking down when the units warms up