Brand new forum user here, so hopefully I'll figure this out. I have a 99 ranger 4x4 with the 4.0 V6 with 99K original. I installed a K & N cold air intake and my AIC valve started howling like a banshee. I replaced with one from Autozone ($40 or 50 something like that). That was 2 months ago and now the replaced one is doing it just not as loud. I took it off and soaked it in starting fluid which only quieted it for a day. Now its back to a loud hum at idle. My question---- will an OEM model from Ford work better? Is there a quality difference between the 2? I had never even heard of an auto idle control valve before this. Any suggestions?

 

Welcome to the forum

1986 thru 2011 Rangers came with 200% flow Cold Air Intake, just FYI

Remove the K&N air filter from the end of the tube
Start engine, go for a drive if needed
If noise is gone the air filter is too small, under 100% flow

 

Yep...Those HAI are nothing but trouble.

 

Stock AirFilterBox is as good as it gets;
do NOT waste money+time on aftermarket CAIs.