Apex will not stay running

[Bicycle_Mafia]

Just put a Apex engine in my Polaris RZR and I cant get it to stay running. When it turns on, it revs up and slowly goes down to idle and then keeps dropping lower rpm until it finally dies. I turn the key off and then re start the engine and it does it the same way every time. It will not let me rev it up either. It sputter real bad and kills it when I try to open the throttle. The only trouble codes that display are 11, 21, 22, 84. I got rid of them all and they dont come up anymore. But still runs like crap. I am using stock rzr fuel pump with 39psi fuel pressure. I have 4 k&n filters on each throttle body and a custom oversized header and two brothers muffler and no fuel tuner at the moment. Someone told me to re prime my oil pump, but I did that (i think) and it didnt change anything and isnt saying I have low oil pressure. Is there another sensor or connector that I have to bypass or anything? I cant figure this out on my own. Need help. Thanks. Also I am in Arkansas with 80 degree weather.

 

[burnoutink]

I had a similar problem ended up being the TPS (throttle position sensor).
Good Luck!

 

[Bicycle_Mafia]

I checked the tps with a voltmeter and highest voltage I could get was like 3.5 volts at full throttle and .6 at no throttle. But I checked the percentage on the gauge and it seems to be working fine.

 

[burnoutink]

In the end my TPS was faulty, it would not put the throttle range to get proper gas.
do you still use the stock display console when you put the apex engine in theRZR?
If so do a TPS test that way and maybe check the throttle range.
Good Luck!