[Grizzly1234]

Hi everyone I’m new here and also new to the Yamaha Grizzly. I just bought a used grizzly 700 2011 fuel injection. When I bought it I new it was idling high but I figured I could just adjust with idle screw. Well idle screw has been broken off so I pulled cover off throttle body and the screw isn’t even touching inside so I know that’s not what it is. I’ve checked throttle cable and it’s not the problem either I actually unhooked cable and it still idles high. I don’t know what else to do so if anyone has experienced this or knows what I can do please help. Thanks

 

[Grizzly1234]

It’s idling so highly that’s it’s grinding gears and jumps when it does go in gear. I have also pulled throttle body off cleaned everything and made sure butterfly was opening and closing properly and it seems to be fine.

 

[dezz]

Could be an air leak between the throttle body and cylinder head. Does the adapter boot have any cracks or tears or loose mounting bolts?

Could be a stuck or broken Idle Air Control (IAC) valve on the throttle body. Remove the IACV from the throttle body and give it a good cleaning with contact/brake cleaner.

If the IACV is needs replacement, you can't buy it separately from the throttle body from Yamaha. You must purchase a complete new throttle body.
BUT, you can purchase the exact same IACV from Suzuki as a separate component. The King Quad 700/750 uses the same valve. Use Google to find out the Suzuki part number you need.

 

[Grizzly1234]

Thanks Dezz I’m going to check for air leaks when I get home and clean the valve if that doesn’t work I don’t know what to do. If it had a air leak it looks like it would idle up and down to me this is a steady high idle.

 

[Grizzly1234]

Well I have checked for any air leaks and there is no leaks. I did unplug the IAC valve while engine was running and there was no change in the way it was running. I took valve out and cleaned but it wasn’t that dirty so I plugged it back in and cycled the key with it out of the throttle body and valve did not move or anything but it is getting hot after a few minutes of it being switched on. Does this mean that the valve is bad?

 

[dezz]

Well I have checked for any air leaks and there is no leaks. I did unplug the IAC valve while engine was running and there was no change in the way it was running. I took valve out and cleaned but it wasn’t that dirty so I plugged it back in and cycled the key with it out of the throttle body and valve did not move or anything but it is getting hot after a few minutes of it being switched on. Does this mean that the valve is bad?

I am not sure if that would mean a bad IACV, but the plunger should move in/out when you plug it in or cycle the key on/off..... at least to my knowledge it should. That's how I would test a IACV on a automotive engine. Or at least bench test it by hooking up wires from a battery to the IACV to see if it moves. But since yours is getting hot, I would assume it is getting electrical power.

Try this if possible. Remove the IACV from the throttle body. Keep the electrical connector on it. Start the engine. Put a finger over the hole where the IACV mounts on the throttle body. See if the RPM changes. The engine RPM should drop.
While your doing this, monitor the plunger on the IACV. It should move in/out if working properly.

 

[dezz]

One other thing to check. Inspect the valve clearances. This is a maintenance task that should be completed, but is often the most overlooked and not completed because of the work load involved.

 

[Grizzly1234]

Yeah I tried to start it with it off when I was checking it and it shot a ball of fire out at me so I didn’t try it again. Lol

 

[Ridgway81432]

Welcome from Colorado.
This may help for a new part, click on the art name for details.
https://www.partzilla.com/catalog/suzuki/atv/2011/kingquad-lt-a750xl1/throttle-body

 

[Fantic212]

Don't know if you ever got this fixed but check for a broken wire at the back of the ISC valve as found that with mine today. The main wiring loom doesn't seem to be quite long enough going under the air box to the valve. So the wire gets pulled hard back on its self, then breaks off. Mine was pink and blue in colour.