I have a rough idle. My buddy is gonna help me remove and clean the air bypass valve.

He warned me that sometimes after removing them you find out you need a new one. Anyone experienced this? Or does cleaning the air bypass valve with carb cleaner and a brush usually work fine?

Thanks.

 

I have found that it is difficult to really get them clean. You don't want to soak the whole valve (assuming you were going to remove valve to clean) or you will damage the solenoid. I spray cleaner in the throttle air port while the engine is running. I would just replace the valve if your sure that's the problem - they're not that expensive. If you choose to clean, be aware that some years have teflon coated throttle bores so make sure the cleaner is compatible or you will remove the coating. (BTW, even the teflon coated bores get gummed up. I also find the most of the rough idle and hesitation problems come from build ups around the throttle plate. With engine off, hold throttle wide open and wipe bore clean.
Finally when you are spraying cleaner in engine while running, I like to spray in enough to stall engine (while holding throttle partly open) then let it soak for a while. You should also plan on changing out the spark plugs when your done.

 

[updated:LAST EDITED ON 27-Jul-02 AT 11:56 AM (EST)]Cool. OK - I'll clean up around the throttle plate too.

I have a slight jerky hesitation when accelerating and an idle that surges high/low when idling in park. That surging is what my Ford mechanic buddy says is typical of an old/dirty bypass valve. He also says only buy Ford parts on this valve as opposed to Schucks. Fine. We'll try cleaning first. I was hoping the clean valve will also solve the jerky driving (happens at about 30MPH typically). Seems like dirty injectors, too, maybe.

Yes, I figured I would also buy those Bosch Platnum 4 plugs I've been reading about on this board. What the Hell..!

 

If the problem at 30MPH remains (after you clean IAC), check the Throttle Position Sensor (TPS). Sometimes when you drive the same route for a long time the throttle ends up staying in the same postion a lot. For example if most of your daily commute is at 30 -45 MPH the throttle may spend most of life at, say, 20% open. What this does is wears out the contact (wiper) at the 20% position. This can cause a stumble or hesitation while not setting any code. You can check this with a scanner that displays TPS voltage. With engine off slowly move throttle from closed to WOT while watching volts. If you see erratic voltage (should be nice steady movement) then repalce TPS. If you don't have access to a scanner, I would just replace the TPS because its cheaper than taking into shop and paying for an hour of labor.
My two-cents.