I've been hearing a loud whistling sound when my car is running. I was looking at the AIR pump today and the short 90* tube coming off the side of it is just there with nothing on the end of it. Is is supposed to be like that? My car is a '99 and it had a high flow lid on it when I got it.

 

Mine did the same thing, I had the supplied filter for the hose, which was tucked behind my proportioning valve. But I had pacesetter LT's & TD's installed so no more AIR provisions. I pulled the fuse for a couple of weeks, because it was driving me crazy, and making my volts bounce. Then I just removed it all together, and had the SES codes tuned out for good measure. (Never threw any, but they usually do.)

 

not sure what elbow you're talking about.

but the air pump should only run for a few minutes after start up.

pull the fuse and see if the sound goes away...if not...it's something else.

alhtough the lid could easily cause a noise...that's part of the fun