318ti.org forum (http://www.318ti.org/forum/index.php)
-   Engine (http://www.318ti.org/forum/forumdisplay.php?f=28)
-   -   Strange blowing/vaccuum noise from M44 ti (http://www.318ti.org/forum/showthread.php?t=26629)

Variance 05-05-2009 11:37 PM

Strange blowing/vaccuum noise from M44 ti
 
Hey guys,
I recently got a CEL and started hearing a strange vaccuum noise from my engine bay. The engine still runs like normal, and the noise stops after sitting at idle for a couple minutes. I tracked it down to the part in the center of the following picture:

http://img11.imageshack.us/img11/7924/dscf0963i.jpg

When I stick my hand next to it, I feel air blowing out the sides of the "lid", and the noise subsides when I push down on the top. I took a quick video to show this and the noise:
http://www.youtube.com/watch?v=5nkN8wYPpVY

Any ideas what the problem might be, and is it safe to drive the car in the meantime?

b.u.ti-ful 05-05-2009 11:49 PM

Secondary airpump.

cooljess76 wrote how to fix it somewhere on this site.

I seem to remember the fix was to grind off the rivets and bolt down the lid.

Variance 05-05-2009 11:55 PM

That seems kinda... iffy. If it's an airpump, I guess it's part of the emissions system? Does anybody know what would cause it to randomly start doing this?

b.u.ti-ful 05-12-2009 08:26 PM

Any progress?

cooljess76 05-12-2009 08:39 PM

The secondary air pump is basically composed of a series of plates that are held together by 6 aluminum rivets to make up the body of the actual pump. The rivets tend to break, allowing the plates to separate and leak air. The reason that you only hear it momentairily after startup is because it only runs for about 30 seconds after the car has been started on a cold engine. You can easily fix the problem by first removing the secondary air pump, removing the broken rivets and possibly drilling out the others. Then replace them with machine screws and locknuts. This should eliminate any problems and extinguish your CEL. Depending on how long you've known the noise to be there, you may consider taking the pump apart and cleaning the internals with brake cleaner. It's not absolutely necessary, but just a suggestion. Also, while you're working in that area, you may want to replace the ribbed rubber boot between the MAF and the ASC valve as it's known to crack and give you misfire codes as well as trigger a CEL. Good Luck, sorry I came in so late.


All times are GMT +1. The time now is 12:36 PM.

vBulletin Version 3.8.8
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©1999 - 2024, 318ti.org