Whats that whistling type sound that the 305's make at an idle (low RPMs maybe 500-ish) usually after they warm up. Mine does it, my father's did it, and a few other's I happen to hear at a stoplight or something of the sort do it. It doesn't bother me, I kinda like it. I'm just wondering what it is. I listened around, but can't find the source. I'd appreciate it if anyone knew, but if not, no big deal. I'm just really curious about what it is.

If your 305 is trottle body which i assume it is. Off of the air box that holds the air filter there is supposed to be a rounded off square looking box that connects to the part where the air comes into the intake. If that piece is missing it will tend to make a whistling noise while it is taking in air. Cause i have a 305 in mine for now and it doesn't make it but i have that silencer box on mine. So maybe that helps if not i at a loss cause i don't think mine makes it.

Its got a rochester 4bbl carb, as did my father's.... If you want I can record it, and make it available to hear online.

Pete,

I think I know the sound too. My 86 does it. I haven't been able to isolate where it's coming form either. But it seems to be related to one of the accessories. It's either the waterpump or the powersteering pump I think. That or just a worn belt running over the pulleys. Drives me batty as stop lights....

mine does it too, i kinda always thought it was the air tubes that run through the cat

Good thought. But my pump locked up and broke the belt last year. I've never fixed it and I still have the noise.....

I tried listening around again, but still no luck. It does seem to be coming from the lower passenger's side of the engine. For those who don't know what I'm talking about I recorded my engine, and transfered it onto my computer. I'll soon make it available to listen to online.

Suppose that's the AIR pump????

my 93 305 doesn't whistle at idle, neither does my friend's 89 5.0...

Maybe I just can't hear anymore, haha

the idle has to be really low (400-500 rpm) mine is set at 475 rpm.

The lower the rpm, the louder the whistle is. Its starts to whistle at a little over 500.

i spent 4 hours going over my car yesterday top to bottom. i actually layed down under the car while it was running and still cant find the whistle. you all know damn well chevrolet did this to drive us all crazy right? :jump3:

Are you trying to find the whistling, or are you trying to find the source of the whistling? If you're trying to find the whistle I'm talking about, then it's able to be heard outside of the car (or in it) when at idle (as I've said if the idle's low enough). If you can't hear it then your idle is set too high, or you don't have whatever it is that's making the whistling. I can't believe you spent 4 hours searching. A very dedicated person you are. :-)


If this helps anybody, I've made it available to listen to the whistling. I recorded a 30 second audio clip of my engine, and it's low idle whistle. It's somewhat loud because I placed the mic right under the hood. Just click below:

Caprice Engine Whistle (http://www.freewebs.com/petea/engwhist.mp3)



I just bought an 85 Caprice wagon from a neighbor for $250 (I'm gonna parts it out. Its got 4 new tires, and a freshly rebuilt tranny, and I need both) And it does the same thing after its warmed up, and idling nice and low (not sure about the rpms, it doesn't have a tach. Odds are 500 or less)

quote: I can't believe you spent 4 hours searching. A very dedicated person you are. :-)


Well I wouldn’t say that, bored more like it :licka: I was actually screwing around, rotating the tires and shit. I decided to check the tranny fluid and I heard the whistle, and curiosity took over. on a sad note my tranny is starting to over rev when shifting into 2 and 3 :mad:

I noticed something new. If the idle drops to about 300 RPM, then the whistling fades to almost nothing. I dont know if this helps at all, but hey, I figured I'd add it just in case ;-)

Caprice Engine Whistle (http://www.freewebs.com/petea/engwhist.mp3)

I noticed something new. If the idle drops to about 300 RPM, then the whistling fades to almost nothing. I dont know if this helps at all, but hey, I figured I'd add it just in case ;-)

Caprice Engine Whistle (http://www.freewebs.com/petea/engwhist.mp3)
Why is your idle so low? My emission label states 650 RPM in drive. Maybe its the carb sucking air at such a low RPM. I have a 81 w/305 and I do not have a whistle at all. I still have all the emission equipment on it. Sounds like you have a vaccum leak.

The label on mine says 500 RPM, I lowered it down to 300 just to see what would happen at that low of an idle (experimenting). I brought it back up to a little below 500 now. Theres no vaccume leaks (that I know of at least). When I got the car about three, maybe four years ago, I went and replaced all cracked, and stiff vaccum hoses. I've also recently rebuilt the carb, and have a new base gasket as well.


Caprice Engine Whistle (http://www.freewebs.com/petea/engwhist.mp3)