Hissing sound under car? wtf?

djcontra · 12-05-2003, 08:08 PM

Guys, I'm hearing a loud hissing sound, like a disconnected air or vaccum hose under the car somewhere. What parts might I look at to track it down? It sounds like it might be near the tranny area, or oil pan.

Jon@Bimmersport · 12-05-2003, 10:22 PM

i heard a "meeeoooow" while driving my dads car when we were going to the gym....out of no where it crawls from under the car when i park

87e30 · 12-05-2003, 10:35 PM

if the e36 has an external fuel pump try that, I know on e30s when the external one goes bad it hisses

moerom · 12-05-2003, 10:43 PM

Could be a boost leak! When it gets cold, hoses tend to contract and move around.
I have a hissing sound too sometimes, and I have to do a test to make sure I'm not losing boost!

djcontra · 12-06-2003, 04:37 PM

Quote:

Originally posted by moerom
Could be a boost leak! When it gets cold, hoses tend to contract and move around.
I have a hissing sound too sometimes, and I have to do a test to make sure I'm not losing boost!

It shouldn't be a boost leak because I'm using all new plumbing and silicone cuplings (I just installed a new intercooler yesterday). Plus the sound is far away from the engine. I'll have to find out if the brake system, or tranny uses any vaccum hoses or anything...hmmm...
I'm not going to drive until I get it sorted out though..

blacknblue-e30 · 12-06-2003, 04:50 PM

crack in the exhaust?

djcontra · 12-06-2003, 05:15 PM

I'll check that out...I sure hope there isn't a crack

Gizmo · 12-07-2003, 11:14 AM

It is most probably your fuel pump, have you replaced it before?

djcontra · 12-07-2003, 01:29 PM

Quote:

Originally posted by Gizmo
It is most probably your fuel pump, have you replaced it before?

No I havent, but isn't the fuel pump near the rear of the car, by the gas tank?

Jase · 12-07-2003, 01:41 PM

Quote:

Originally posted by 87e30
if the e36 has an external fuel pump try that, I know on e30s when the external one goes bad it hisses

that happened to my e30 too.I'd check the feul pump.Mine was near the back of the drivers door
Jase

djcontra · 12-07-2003, 02:29 PM

Ok cool, I'll check that. It's very possible that my fuel pump might be going because of the heavy load it endures now due to the s/c

Jase · 12-07-2003, 03:06 PM

I had a s/c on my last car.I needed to upgrade the feul pump.
Jase

A~G · 12-09-2003, 04:36 AM

I'd say its an exhaust problem ..

My car sounds like a fuken airplane. The bend-pipe (don't know the exact name) but its the part of the exhaust system that acts as a shock absorber is broken... not to mention the numerous holes all the way to the muffler