whistle sound at warm up

[silversleeper]

this is kind of hard for me to describe to you ppl, but during these wonderful freezing cold morning starts, the engine kind makes a "whirring" or a whistle sound during its warm up. engine hangs at 2500-2900 rpm and u can hear the sound, but eventually goes away after warmed up.

now, i kinda shot myself in the foot when i painted my intake mani and didnt install new gaskets, so that is my main guess. i just havent found a good way to test it yet. im thinkin of spraying some seafoam or similar product where the mani meets the head, but i wanted to check wit u all first to see if anyones had a similar experience.

[madjurgen]

i get this too, mine is oscillating

[Jand3rson]

Are you sure it's not just very cold, squeaky belts? My car sometimes squeaks in the mornings when it's really cold, it could sound like a whistle, though.

[silversleeper]

No belt noises. They are all in fine condition... not sure bout my timing belt though, but I doubt that would make any noise, if any. The previous owner failed to provide me with service records and he did not know if and when the timing belt was last changed. I am at 70,600 on the clock, I think I will just change it for peace of mind when it gets a bit warmer in this area.

But back to the whistle... Is my method of testing the leak okay? Basically spraying any type of intake cleaner near gasket areas and on vacuum lines to listen for a change in idle.

What do the pros do to test for leaks?

[arsevader]

this is kind of hard for me to describe to you ppl, but during these wonderful freezing cold morning starts, the engine kind makes a "whirring" or a whistle sound during its warm up. engine hangs at 2500-2900 rpm and u can hear the sound, but eventually goes away after warmed up.

now, i kinda shot myself in the foot when i painted my intake mani and didnt install new gaskets, so that is my main guess. i just havent found a good way to test it yet. im thinkin of spraying some seafoam or similar product where the mani meets the head, but i wanted to check wit u all first to see if anyones had a similar experience.

Cold alternators sometimes whistle.

[arsevader]

this is kind of hard for me to describe to you ppl, but during these wonderful freezing cold morning starts, the engine kind makes a "whirring" or a whistle sound during its warm up. engine hangs at 2500-2900 rpm and u can hear the sound, but eventually goes away after warmed up.

now, i kinda shot myself in the foot when i painted my intake mani and didnt install new gaskets, so that is my main guess. i just havent found a good way to test it yet. im thinkin of spraying some seafoam or similar product where the mani meets the head, but i wanted to check wit u all first to see if anyones had a similar experience.

Cold alternators sometimes whistle.

[silversleeper]

okay, i noticed it while warm today in traffic. and to top that off, during my cold startups, something in the engine bay knocks like crazy, but its not the motor (i hope). sounds like a broken belt slapping the shit out of something, but the sound goes away at higher rpms (2500+rpm). i need some warm weather so i can pop my hood and take a look.

[EtaSport]

knocking sounds like something is loose. Check the t-belt tensioner. Mine was loose and caused similar noises.

Intake could possibly be leaking. If the leak is on the bottom it is unlikely you will find it. Did you make sure the intake vent tube is properly attached? Those o-rings get pinched and sliced sometimes when re-installed. Check the vacuum at idle.

[silversleeper]

the intake vent tube

?

Are you referring to that bitch tube that goes up from the block into the bottom of the manifold?

[EtaSport]

Yes

[Charlie]

You guys are clearly missing the obvious cause.

http://www.ebaumsworld.com/bubbrubb.html

-Charlie

[Dave]

I think BubbRubb is a new member here - by the name of UniqueBMW.

[Il Duce]

You guys are clearly missing the obvious cause.

http://www.ebaumsworld.com/bubbrubb.html

-Charlie

thanks charlie.



wooooooooooooo wooooooooooooooooooooooooooooooooooooooo

[silversleeper]

I believe this is a more accurate description of it...

[silversleeper]

btw, loud tapping was the damn spark plug wire cover (on the distributor) being smacked by the fan, the clip came undone.

Whistle is still there. I doubt its that thing we discussed (pipe from block to bottom of intake mani) because I made sure it was installed securely. it was so annoying, but it is in. And if it wasn't, wouldnt something leak from it?