Try taking the PCIII off, that certainly isn't gonna help. Get it running right without the PCIII then put it back on. If it's done it ever since you bought it then it could be an adjustment. Try messing with those three screws and see if it helps, just remember how they're adjusted right now so you can put em back if necessary.

My manual calls those valves "starter valves." Might wanna try and find out why they aren't going all the way back in, that could be your problem. I guess it's possible that they could be all plugged up. They slide out if you take off the bracket that moves them then unscrew the base nuts that hole them into the throttle body.

 

I took the PCIII off when my buddy came in to test ride it. It helped with revving (it revs more freely now) but not with the way it was idling.

i guess im going to have to take them out. i hope it's not hard to do so. I think I'm going to need a compressed air device to clean the valve bypass unit.

 

Ok. I went to the garage and to my knowledge the wax unit is at fault.
I have unscrewed the idle adjustment screw (****) and, as you can see from the pix, I've used an extension tool to push down on the metal arm thats linked to the wax unit, and I was able to fully close the valves. Below are two similar looking pix: one with the extension tool used to push down on the rail and other with the extension tool removed (no pressure on the rail). My question is: is the wax unit supposed to push up on the rail (circled) in order to create resistance (close the valves), so an accurate adjustment with the idle **** could be done? Is it blown or could I just adjust the wax unit somehow in order for it to work the way it supposed to? I hope I dont need to replace it, but I'll do it if thats the case.

 

Whichever way closes those valves is the way it's supposed to move. I would do two things before I bought a new wax unit. I'm not sure if that is adjustable, you'd have to inspect it yourself and see.

Push those valves closed and see if the idle goes down. If it does go down then take the wax unit off and put it in a pot of water, boil the water, and see if the plunger moves. hold the plunger end out of the water and do a little before and after measurement...

If the plunger doesn't move then the wax unit is toast, get a new one.

80 bucks sounds a little cheap but here's the only one i could find on ebay,

http://cgi.ebay.com/ebaymotors/HONDA...Q5fAccessories

 

cool. will do. all i gotta do is to take the throttle body off, which is going to be interesting since i never done it.

anyway, i found couple of throttle bodies on ebay for cheaper than the wax unit you posted. do you think any year f4i throttle body would fit my 2004 f4i?

 

You can rebuild the WAX unit (if that's what's wrong), #8: Ron Ayers.

 

i could, but i figure if i spend $50 on the wax unit and i could get the whole throttle body assembly for $60 then i'd just replace the whole thing.. so the questions remains: are 01-05 f4i throttle bodies the same?

 

According to the microfiche, there's two TB types for all years of the F4i, the 16401-MBW-A11 and 16401-MBW-L11. As to the difference between the two, I have no idea. Maybe call & talk to a Honda mechanic.
It does appear that all other componets fit both, so probably they're both identical.

 

perhaps one is made for California models.. hmmm.

 

I don't think so. The only difference I see is to the vacuum line routing.