HI, I was just wondering if this is normal.. When I first start the car for the day (or after sitting a while) I hear a whine, sounds like the fuel pump. It isn't very loud, hard to hear, but sort of high pitched. The sound goes away after idling for like 2-3 minutes. While its making the sound if I rev the engine and take my foot off the gas, the sound stops until the rpms drop back to idle then it starts again. Its like it turns off and starts again (whatever is making the sound). One thing I noticed at night is that when I rev it and release the gas, when it drops back to idle to turn back on, the lights dim just slightly. So whatever is making the sound must take some power. Is this all normal??

 

AIR pump. It's electric, it will turn off when the car is warmed, and they can make a whine. I hear they get louder as they get older too, but I haven't witnessed it firsthand to know for sure.

No need to worry.

 

Maybe the IAC (Idle Air Control) valve - it needs to open when the throttle is closed, and closes when the throttle is opened. It doesn't use much power, though. The IAC noise is more prevalent with aftermarket throttle bodies and CAI's. Mine makes a distinctive "whistle" under the circumstances that you describe, with the Edelbrock TB and SLP CAI. It goes away after a minute or so of running.

 

Thanks for the input. BTW I have all stock intake and throttle body parts. If it doesn't take much power why would my lights dim when it turns on?

 

My 93 Z does the same thing, or at least the two conditions sound the same as mine. I hear more of a lower-pitched humming, almost like a fan, that quits when the car gets warm. My Z also does the same thing with the lights, except mine does it when you're pulling up to a stop sign (decelerating), just before you get to a stop (~ 5mph), the lights go dim for a split second. I dismissed it as a minor, minor electrical issue, but that's just me.

 

A.I.R. pump. It runs when you start up to blow air in the cats to heat them up faster so they can do their job.

 

AIR pump most likely...

When you first start the car in the morning.. it will run for about 2 min maybe.

 

Mine's done that since new. I've never really worried about it, and always considered it "normal", although I don't know for sure what causes it.

 

it's proab the AIR pump. mine does it moreso when it's cold on outside. their was a bullitin on them up till 96 i think. water gets inside them. only other thing i can think of is maybe low power steering fluid.

 

That's the sound of Chuck Norris's foot slicing through the air.

 

Definitly air pump, my car does the same thing when I start it up and its in the monring and it was cold outside. They make a loud *** buzzing noise for like 5 seconds and then go away, yours prolly varies in noise but thats prolly what it is.