What is the part number for 2003 4.6L air bypass valve? I installed S&B CAI and had to mod air bypass valve in the process - I'd like to order a new one incase I have turn it back to stock.

 

You mean the idle air control valve (IAC)?

MOTORCRAFT Part # CX1789 {#2L1E9F715BA, 2L1Z9F715BA, CX1823E}
2L1E-9F715-BA

$89.79 at rockauto.com.

http://www.rockauto.com/catalog/moreinfo.php?pk=382755

 

thanks - but IAC is different.

Here is the pic:

 

That doesn't look like any IAC I've ever seen!

 

Obviously this is kind of a mystery part.

See this thread - the part is called "the piece that no ones knows the hell it's for"

http://www.fordf150.net/howto/throttlebodyclean.php

 

Oh - it goes between the intake tube and the IAC, right? It's probably an intake muffler or some kind of filter or oil/vapor separator.

 

Mine is a bit different...



But I have looked inside them, and see no type of separator or filter. Looks to be some kind of muffler to reduce noise from the IAC tract. Yours may be different though, sure looks different.

 

Yep, that's right. The black box above (piggingtons pic), serves the same purpose as Toyz pic. They're both IAC Mufflers. The difference is, - the black box mufflers are only used on the 4.6L's. The round type are only used on the 5.4L's.

 

So, if it's just a muffler I assume it's optional and you could use a direct connection?

 

Nope. Well, you can, but you'll hear the IAC thru the intake. Some of them sound like a fog horn, some whistle.

Some won't make a peep right away, but eventually they get noisy without one. Specially the 4six with the IAC right next to the intake tube.

 

If he doesn't care about the noise the washoobi makes, he shouldn't care about an unmuffled IAC.............

 

Now that I look back, I think he is still using the muffler which he didn't have to modify.. Looks like he had to modify/cut the pre bent hard line hose for the new intake and if he wants to go back the stock intake, he'll need the oem hose...? I think that's what hes asking. I don't know how he could have modified the muffler, think hes referring to the line itself. If I remember right... before my knowledge of the gotts intake, or any knowledge on intake systems really... I installed a beautiful Chinese warm air intake with open filter on my last truck... and I think I remember having to cut the line that goes to the IAC since it was a hard line and shaped wrong for where it's new placement was on the intake. It was cut and replaced with a soft line that came with the intake.

 

Actually I had to modify "IAC muffler" by cutting the hard plastic line going into it.

Based on the responses here, if I ever go to stock again, I don't have to worry about this - I can just use the soft hose to connect it to stock intake.

 

Sounds logical to me - when all it's doing is carrying air it shouldn't matter whether it's a hard line or a rubber hose - as long as the hose is rigid enough so it won't collapse under suction.