weird whistle under part throttle...

[slater]

having a weird issue... noticed it when outside temps start to get to around 0ºC, but tonight when it was -28.5ºC it was pretty bad. the issue is a steady-pitched whistle coming from the engine - does not change in pitch, always the same pitch. only happens at part-throttle (like 10%), letting off the throttle or applying more relieves the noise.

it can't be rotational as the pitch does not change. any ideas?

peter

[alexandre]

I don't remember if you recently replaced it or not, but it could be the CCV - whistling is a symptom. I did a lot of short trips in the days leading to this deep freeze and my CCV was partially clogged Tuesday morning. Similar symptoms. Plus the mayo in the crankcase was frozen.

Solution is to open the oil cap and take out the dipstick. Let engine run in neutral until coolant reaches 12 oclock. Listen for any weird noises and turn engine off if anything seems weird. This will warm things up in the engine bay and melt the mayo in the system.

After that you need an italian tune-up. :biggrin

[Pip]

Hmm. I had a partial throttle whistle that I believed was caused by the after market intake because I had all new boots, but not sure it changed based on temps and I live in Northern CA so not very cold.

[Fenrir]

Hmm. I had a partial throttle whistle that I believed was caused by the after market intake because I had all new boots, but not sure it changed based on temps and I live in Northern CA so not very cold.

Ditto. I have a small whistle on mine caused by my AFE intake. It's at all temps and early on the throttle. All hoses and boots are new.

You could possibly check your intake boots for cracks or fitment and press from there. I also agree with Alexandre on the CCV. That.. and a good ole Italian tune is always fun :)

[slater]

I don't remember if you recently replaced it or not, but it could be the CCV - whistling is a symptom. I did a lot of short trips in the days leading to this deep freeze and my CCV was partially clogged Tuesday morning. Similar symptoms. Plus the mayo in the crankcase was frozen.

Solution is to open the oil cap and take out the dipstick. Let engine run in neutral until coolant reaches 12 oclock. Listen for any weird noises and turn engine off if anything seems weird. This will warm things up in the engine bay and melt the mayo in the system.

After that you need an italian tune-up. :biggrin

LOL @ the italian tune-up. :)

my CCV is gone at this point - running an ADD W1 catch can w/ PCV valve. not entirely pleased with the can, but that is beside the point - the whistling started while i still had the OE CCV plumbed into the system...

i forgot to mention, that after the car is good and warmed up (like, say 10+ minutes of driving), the noise is gone. however, the colder it is outside, the longer it persists.



Hmm. I had a partial throttle whistle that I believed was caused by the after market intake because I had all new boots, but not sure it changed based on temps and I live in Northern CA so not very cold.

Ditto. I have a small whistle on mine caused by my AFE intake. It's at all temps and early on the throttle. All hoses and boots are new.

You could possibly check your intake boots for cracks or fitment and press from there. I also agree with Alexandre on the CCV. That.. and a good ole Italian tune is always fun :)

i have an aFe Pro Dry S and i actually put the stock intake back in to troubleshoot - happens with either intake. my intake boots are about 7 months old.


wondering if i have a vacuum leak elsewhere - perhaps at the fuel filter? that is next on my list of things to replace. it is hard to determine exactly where the whistle is coming from.

peter

[ELCID86]

I had a slight whistle in mine yesterday :facepalm . First I've noticed it (and first it's been this cold).

[slater]

I had a slight whistle in mine yesterday :facepalm . First I've noticed it (and first it's been this cold).

we'll get through it together, shawn! :)

peter

[ELCID86]

we'll get through it together, shawn! :)

peter

Deal.

[slater]

snagged a rough video. shawn, does yours sound like this? note the temp gauge, still rising (i had been driving for maybe 2-3 minutes at this point).


http://www.youtube.com/watch?v=eJ_u52yYiRM

peter

[ELCID86]

Very similar. Faint and intermittent. I was listening to a podcast and actually thought it was mic feedback, etc.

[slater]

update on this: i had 6hrs in the car yesterday, the first 4-5hrs with slightly warmer temps (-5C), and no whistling. near the end of the journey last night it got down to -15C very quickly and even though the car was fully warmed up (had been on the road for 2.5hrs at this point), the whistling returned when it got colder... this typically went away when the engine was warmed up! very strange.

peter

[SoCalZman]

my car does the same thing. I found a hole in my lower intake tube. I changed both out. That helped the noise a lot, but it is still there. I think this is a common "issue: with the E46.

[slater]

my car does the same thing. I found a hole in my lower intake tube. I changed both out. That helped the noise a lot, but it is still there. I think this is a common "issue: with the E46.

i replaced my intake boots last may, so i would be extremely surprised (and disappointed) to find a tear in one of them. going to check this weekend, regardless...

peter

[slater]

still getting this. goes away under more throttle, or less throttle... have not been able to track it down yet.

anyone else?

[BMWCurves]

No idea. Your video's not private so I can't view it.

[anandoc]

still getting this. goes away under more throttle, or less throttle... have not been able to track it down yet.

anyone else?

And the whistling sound returns lol. I remember you and I sharing this exact symptom last winter. Fortunately, I have not had this whistling sound return this winter...so far.

[ELCID86]

I've noticed this again the past few times it's been in the 20*F range.


---
"ZHP is a garbage option anyway- just some cosmetic upgrades with a different cam and diff to claw back some of the performance lost fitting those hideous and heavy wheels. Any 330 with a 3.46 diff will smoke a ZHP every time. The whole Mafia thing reeks of childish behavior." - an e46fanatic

[slater]

No idea. Your video's not private so I can't view it.

i think it is private, but i've linked to it - should work? i'll double-check.



And the whistling sound returns lol. I remember you and I sharing this exact symptom last winter. Fortunately, I have not had this whistling sound return this winter...so far.

weird! and yep, it returned - seems louder than last year, but that's likely due to the stiffer mounts transmitting more noise. but it doesn't do it as much as it did last year. hmmm.



I've noticed this again the past few times it's been in the 20*F range.

i'm sure it's not an Imola Thing... ;)

[BMWCurves]

Whoops, I meant it is private, and as a result, I can't view it in your older post.

[anandoc]

Whoops, I meant it is private, and as a result, I can't view it in your older post.

Peter, you are supposed to mark it as 'unlisted' - not 'private' on youtube. If it is 'private' we would not be able to view it.

[slater]

Peter, you are supposed to mark it as 'unlisted' - not 'private' on youtube. If it is 'private' we would not be able to view it.

i finally just checked, and it was marked as 'private' - i've just set it to 'unlisted'. does it work now? :)

[BMWCurves]

Yup! But hell if I know what that noise is, it's very strange. It sounds like a warning sound or something in the video. My guess would be a vacuum leak somewhere, since it's throttle dependent, but I really couldn't say for sure.

[slater]

Yup! But hell if I know what that noise is, it's very strange. It sounds like a warning sound or something in the video. My guess would be a vacuum leak somewhere, since it's throttle dependent, but I really couldn't say for sure.

yeah. i've been all through the vacuum lines. it's a weird one! it does not change pitch - doesn't matter what speed you're going. that's the weird part!

[ELCID86]

I just bought a smoke machine from drummr8. Chasing a code...would be nice if it also revealed this leak/noise source.


---
"ZHP is a garbage option anyway- just some cosmetic upgrades with a different cam and diff to claw back some of the performance lost fitting those hideous and heavy wheels. Any 330 with a 3.46 diff will smoke a ZHP every time. The whole Mafia thing reeks of childish behavior." - an e46fanatic

[slater]

I just bought a smoke machine from drummr8. Chasing a code...would be nice if it also revealed this leak/noise source.

ooh, cool! definitely post up your findings, i am curious! :)

[ELCID86]

ooh, cool! definitely post up your findings, i am curious! :)

Will do. Got the mineral oil last night. I probably won't (and shouldn't) get to it this w/e as its my 29th anniversary! Taken the Mrs out of town on an overnight for dinner and Shakespeare.


---
"ZHP is a garbage option anyway- just some cosmetic upgrades with a different cam and diff to claw back some of the performance lost fitting those hideous and heavy wheels. Any 330 with a 3.46 diff will smoke a ZHP every time. The whole Mafia thing reeks of childish behavior." - an e46fanatic

[slater]

Will do. Got the mineral oil last night. I probably won't (and shouldn't) get to it this w/e as its my 29th anniversary! Taken the Mrs out of town on an overnight for dinner and Shakespeare.

awesome, sounds like the kind of anniversary trip my wife and i would like too. :)

and CONGRATS!!! :cheers