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Discussion Starter #1 (Edited)
Ok. I am officially stumped. Quad will not start.

I have replaced:
-spark plug
-injector
-Throttle Position Sensor

I checked:
-fuel pump,
-roll over sensor
-Air Idle Control Valve

I noticed the Air Idle control valve gets very hot. Nobody seems to sell just the AIC valve. Yamaha wants you to buy the entire throttle body assembly. I bought a similar AIC valve (made for yamahas outboard boat engines and tried to modify it the tip to match factory one....didnt do anything but that one got hot as well. No idea. Im probably going to take it in, but would like to know if anyone has done/checked what I have? And what to look out for.
Also: when I remove the tube from the AIC valve and use my finger to modulate air flow the quad will start. It will idle but as soon as I hit the gas a little it dies.
 

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When you replaced the TPS did you make sure it was placed properly to get the proper voltage?
 

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Discussion Starter #4
No matter how I placed it, using the smallest of inrements, it didnt change. I will try to read the voltage though and find the sweet spot.
I read that if you remove the sensor altogether the bike will revert to a different map allowing it to still run. tried it...didn't work.
 

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Talk to Kilroy. He can get you a sweet little plugin that makes testing it 1000x easier and will ensure it's spot on. if it's off the bike runs crappy to say the least.
 

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Controlling air flow is all I need. Get the gt thunder valve. It's the big gray air hose that wraps around the TB right?

Sent from my SM-G970U using Tapatalk
 

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Discussion Starter #7
@Sheerider11 yes thats the one I think. It comes off of the AIC valve. I used my thumb to partially block it and it fired up. trouble is it wouldnt stay on when I applied even a little bit of throttle. Maybe then it comes down to getting the TPS sensor worked out once I can get it running? Ill have to try the gt valve.
 
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