Nytro MCX 270 mid range rpm cut out HELP!

[davej]

Hey guys, i need some help. I bought a 2009 nytro mtx with a mcx 270 kit on it this summer. Before i started working on it i ran it lots to make sure it was good and it made boost, went to WOT with not issues.

Now that i have it back together just in time for snow, im having issues.

The issue: starts up and idles fine but hits a wall at 4400ish rpm and sounds like a rev limiter/stutterbox. It doesnt matter if i hammer on it or slowly rev to that point, thats where it stops. After the revs come back down it struggles to idle then dies.

Fuel pump/filters are good, lots of flow to the injector rail.
Runs on all 3 cylinders (unplugged each coil while running and it ran bad when unplugged)
Fresh premium gasoline
TORS is bypassed
TPS reads 16-87
No codes
Recently changed cr9eix, they look a little black so i know its getting fuel.

Any idea what my issue is? Could it be the coils? Bad secondary injectors? some grounding or power issue with the mcx boost box? Someone recommended the fuel pump and starter relays but it starts fine and i know its getting fuel

Some help with this would be awesome. im stumped.

 

[MrSled]

As I asked on the 2stroke side... are you sure the TORS is bypassed, it sounds like a tight throttle cable setting it off. When you hit that RPM it wont move, right?

 

[davej]

As I asked on the 2stroke side... are you sure the TORS is bypassed, it sounds like a tight throttle cable setting it off. When you hit that RPM it wont move, right?

Yup itll stay there and not move. I unclipped the 2 single connectors and plugged the chassis side into each other. If it was tors or throttle cable, wouldnt it throw a code?

 

[MrSled]

Yup itll stay there and not move. I unclipped the 2 single connectors and plugged the chassis side into each other. If it was tors or throttle cable, wouldnt it throw a code?

With it bypassed it would not throw a code. Plug it back in and see if you get the code.

 

[davej]

With it bypassed it would not throw a code. Plug it back in and see if you get the code.

The previous owner took off the kill switch and had an aftermarket tether, not sure if this affect things. I had the tors wires plugged in yesterday and still no code.
One guy seems certain that it is the ecu, but thats a lot to spend on a whim.

 

[MrSled]

The previous owner took off the kill switch and had an aftermarket tether, not sure if this affect things. I had the tors wires plugged in yesterday and still no code.
One guy seems certain that it is the ecu, but thats a lot to spend on a whim.

For shits and giggle, loosen the throttle cable until there is a pile of slack and then see what it does.

 

[davej]

For shits and giggle, loosen the throttle cable until there is a pile of slack and then see what it does.

Ill do that this evening. I do that using the nut near the valve cover?

 

[MrSled]

Ill do that this evening. I do that using the nut near the valve cover?

You are correct.

 

[davej]

well.... this is embarassing to admit. After testing different things all evening, i found a rag stuffed over a foot into my intake pipe. Im surprised it didnt get into the turbo. I fished it out and voila, runs like a champ.

 

[maim]

glad you found it.

 

[MrSled]

well.... this is embarassing to admit. After testing different things all evening, i found a rag stuffed over a foot into my intake pipe. Im surprised it didnt get into the turbo. I fished it out and voila, runs like a champ.

Lol. At least u found it. #*$&@ happens.