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Idle Air Control (IAC)

TQuentin1 said:
I think I will have to replace this IAC.
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TQ, you may want to try this. Using the throttle grip, open the throttle body 100% and duck tape the grip in that position. Now wad up some paper towel/rag and shove it BEHIND the butterfly (intake runner area). Remember there is an IAC intake hole before the butterfly (air cleaner side) and also IAC hole (output) after the butterfly. When you boot the ECM with a power on signal and then turn it off, that will force step or parks the IAC. Try flushing while you boot and park the IAC a few times. Spraying into the air cleaner side IAC hole, the fluid should come out the IAC exit port.

The ECM must be turned off for about 10 seconds before it will re-intialize the IAC stepper and park.
Sometimes working the motor while flushing helps. There is a lead-screw on the IAC stem that you can only get clean by removing the IAC from the TB intake and brushing it.
 
Hoople said:
TQ, you may want to try this. Using the throttle grip, open the throttle body 100% and duck tape the grip in that position. Now wad up some paper towel/rag and shove it BEHIND the butterfly (intake runner area). Remember there is an IAC intake hole before the butterfly (air cleaner side) and also IAC hole (output) after the butterfly. When you boot the ECM with a power on signal and then turn it off, that will force step or parks the IAC. Try flushing while you boot and park the IAC a few times. Spraying into the air cleaner side IAC hole, the fluid should come out the IAC exit port.

The ECM must be turned off for about 10 seconds before it will re-intialize the IAC stepper and park.
Sometimes working the motor while flushing helps. There is a lead-screw on the IAC stem that you can only get clean by removing the IAC from the TB intake and brushing it.
Click to expand...

Excellent! Thanx Hoop. I will give that a try. Just to make sure I understand:

  1. Tape throttle wide open
  2. Stick wad of paper towel in intake throat behind butterfly
  3. Turn main switch ON
  4. Spray cleaner into outside IAC port while cycling Kill Switch ON.
  5. Repeat #4 several times with min. 10 sec delay between cycles
  6. Remove papertowel wad
  7. Untape throttle
  8. Start engine to clear cleaner spray
  9. Reassemble A/C
Look right?

TQ
 
TQuentin1 said:
Look right?
Click to expand...

TQ, Pretty much so. Yours may also be the same as my 2009, but with the ignition key in the ON position, when I rock the grip kill switch from ON to OFF, the IAC stepper will walk & park. With the air cleaner off, it is very easy to hear. If I then wait a few seconds (about 5), then flip the kill switch to ON then OFF again, once again the stepper motor walks and parks.
I flush the IAC port (air cleaner side) while I walk the stepper back and forth. Most of the crude will come out the "post" inside IAC hole. The paper towels/rag is in place to mop up most of the mess.

It seems to work pretty good but my IAC was sticking and I resorted to removing it and brushing the leadscrew stem with a toothbrush and cleaner. I then put a few drops of teflon lube on the leadscrew threads after cleaning it. Short of replacing the IAC unit with a new one, that seemed to work for me. But of course I had to remove my tank to get at it.
 
Hoople said:
It seems to work pretty good but my IAC was sticking and I resorted to removing it and brushing the leadscrew stem with a toothbrush and cleaner. I then put a few drops of teflon lube on the leadscrew threads after cleaning it. Short of replacing the IAC unit with a new one, that seemed to work for me. But of course I had to remove my tank to get at it.
Click to expand...

Right. I will price them and see if it is worth cleaning or just replacing it. I hate going through all that effort and then having to replace anyway in the not too distant future. Will see how our new Zanotti's replacement (New Castle HD) checks out!!

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TQ
 
Im thinking we need to reroute our head breathers so The Iac goes not get gummed up What do you think Hoop?
 
Great point Jack. When I first got the 2009 Dyna, I would keep the crankcase oil level right on the full mark. Doing that, I would always find some oil in the air cleaner. That sure would gum up my IAC.
 
Well, I finally got tired of trying to clean the gunk out of the IAC. This has become and increasingly frequent task. Additionally, I am not sure that the stepper motor doesn't lose some of its "umph" as it gets older. So I went ahead and got another IAC from HD and swapped it out.

On my bike, the book calls for removing the whole intake module to change out the IAC. I found that I did not have to do this. I did have to remove the air cleaner backing plate, but that is far easier and does not introduce the same sort of possible problems as removing the intake module. There is enough room to remove the old IAC and install the new one with the air cleaner backing plate out of the way.

Since I swapped it out, the engine is back to running right.

TQ
 
Great information here. exactly the process i was looking for to clean my IAC. hopefully this clears up my idle when pulling clutch issue. will report back later!
 
I haven't looked at the IAC before. I do occasionally get erratic idle.
I've never cleaned this so it is probably worth looking at.

Take care,
Dave
 
I found the P0505 on my wife's 2007 sportster had a broken wire in the idle air control motor harness, you can get a replacment harness/connector from napa part # ec113 comes with wires and connector. (the wire breaks internally cant see from outside) its about $24.00 and problem solved on hers
 
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