runs rough

[jsenske]

Anyone know why my 2006 apex runs rough when started cold. After idles for a minute it smoothes out and runs good.

 

[TBay Sledhead]

Mine does the same thing. I cleaned the IAC (idle air control) this year but haven't had it running since to check it out.

 

[jsenske]

Yea that could be a reason. Its the same everytime i start it cold. Idles loww and rough for a minute the cleans right up.

 

[ranger1]

My 06 Attak & my 07 Apex both would do that. Thought thats just the way they are. After it warms up it purrs like a kitten.

 

[Ak Yammy]

Yea that could be a reason. Its the same everytime i start it cold. Idles loww and rough for a minute the cleans right up.

x2

 

[jsenske]

Weird i had an 07 rtx and it always high idled smooth for the first minute or so

 

[ranger1]

The RTX would run rough for about a minute then would idle high until it got warm. What is this IAC that needs to be cleaned anyway? Where is it located & what is the cleaning procedure?

 

[TBay Sledhead]

The Idle Air Control is used to set the idle by controlling air bypassing the butterflies in conjunction with the fuel system. It is controlled by engine coolant and is what gives you the high idle when cold. It is located on the left end of the throttle body assembly, has 2 coolant hoses on the right side, 4 small brass screws on top, 2 hoses on the front that come from the airbox and a black knurled knob on the left to set the idle speed. The brass screws control the opening that bypasses the butterfly and the knurled knob sets the pressure on the flafner inside (I don't know what it's called) that is heated by the coolant which in turn regulates the amount of air going to the brass air control jets. Long winded.
To clean, remove the headlight assembly and the headlight stay. You will see the IAC on the left side of the throttle body assembly. Pinch off the 2 coolant hoses with vise grips and remove (a small amount of coolant will escape. Remove the IAC from the motor and disassemble. If you decide to remove the brass screws make sure that you put an indexing mark so as to set them back to the same position. Clean all the parts and re-assemble. The brass jets should be set with a manometer or by your dealer. I don't know the spec. or if it's in the manual, couldn't find it. I removed mine but was very careful to re-install back to the original setting.When connecting the coolant hose, first install 1 hose then slightly release the pressure on that vise grip and allow coolant to fill the IAC and then install the other hose. Done.

 

[blue er]

similar issue here, the rpm adjusting screw has a o-ring on it mine was torn replace entire screw cleaned out iac and also replaced fuel pump check valve that was leaking back, fires right up perfect now

 

[blue er]

throttle body sync, if your playing with the 4 small screws on top of ficv (iac)
engine must be running and fully warmed up (10 minutes)
there is 4 rubber vacuum caps one on each throttle body.
you sync everything to number 1 cylinder
make sure rpm is 1500 rpm
use a vacuum guage on #1 spec is 27.3kpa-205mmHg. or 8.0708 inhg
if necassary adjust air screw#1 till in spec then continue across moving guage to next cylinder and adjust so it's the same as #1 and so on
when complete readjust rpm if required.
T-Bay on page 2-9 of my manual

 

[ranger1]

Thanks blue er & TB sledhead for the info on where & how to clean the IAC, much appreciated. I will clean mine this weekend & hopefully it will clean it up at cold idle.

 

[02xtreme]

I have the opposite problem. It idles low (almost stalls) after warming up when the coolant starts to flow. Would it be related to the IAC?

 

[TBay Sledhead]

Some guys are saying that cleaning the IAC has cleared that up.