Hissing sound

[CAJ19]

When I hit hard on the gas pedal, a very high hissing sound comes from the engine bay. Tried to check for loose air hose connections but all were in order. Even took out the intake manifold, still could not trace the source of sound. It happens only when the rev reaches >2500rpm. Issit normal for a 525 single vanos to sound like that when you rev hard???? Sifus, please help

 

[three28]

hmmm i reckon that u may have a vaccumm leak somewhere ...my 2 cents ..Check with e34 sifu's like bundy , blackcat and erica..cheersz

 

[535i]

Maybe got snake alive !!!! Serious wor .. last 2 weeks, a baby cobra crept out from my engine bay when I started my car ... Scary mannn .. got baby ... sure got mother wan ... Sorry, hijack thread ..

 

[three28]

Originally posted by 535i@Dec 7 2004, 09:15 PM Maybe got snake alive !!!! Serious wor .. last 2 weeks, a baby cobra crept out from my engine bay when I started my car ... Scary mannn .. got baby ... sure got mother wan ... Sorry, hijack thread ..
Whoa man u must be kiddin ...Damn that is scary mate whoa now got to put some sulphur powder in the engine bay cheers

 

[535i]

I am not kidding !!! I will leave my car at my parent's place (garage, cement, everything ..) when I hv to go outstation.So, I guess, being in a kampung, the natural element takes over.I wouldn't put sulphur if I were u .. A small spark can toast ur BMW .....What abt having a big rat sitting nicely on top of ur injector ??? Yup, got that too .. and guess where .. Basement parking, Cyberjaya ...I think, I want to go for 4D already ....

 

[CAJ19]

checked all vacuum hoses and found to be in good working order. Another problem is the delay in transmission shifting. If I hit the pedal to the floor, it takes about 2-3secs before it shifts. Car vibrates a little on D or R position. RPM constant at about 650. :unsure:

 

[flash]

Originally posted by 535i@Dec 7 2004, 06:10 PM I am not kidding !!! I will leave my car at my parent's place (garage, cement, everything ..) when I hv to go outstation.So, I guess, being in a kampung, the natural element takes over.I wouldn't put sulphur if I were u .. A small spark can toast ur BMW .....What abt having a big rat sitting nicely on top of ur injector ??? Yup, got that too .. and guess where .. Basement parking, Cyberjaya ...I think, I want to go for 4D already ....
Hmmm, a snake and a rat... wonder what next? Perhaps the snake had wanted the rat for its meal?Once had a cat in my engine compartment (previous jalopy)... cud have been hiding from my dogs. Thank god my engine had not made a mince meat out of it when I started the engine. What a mess that wud have been.

 

[Zoggee]

Originally posted by CAJ19@Dec 7 2004, 02:24 PM When I hit hard on the gas pedal, a very high hissing sound comes from the engine bay. Tried to check for loose air hose connections but all were in order. Even took out the intake manifold, still could not trace the source of sound. It happens only when the rev reaches >2500rpm. Issit normal for a 525 single vanos to sound like that when you rev hard???? Sifus, please help
huh..........!!!!???? I oso got the hissing before I broke my engine...!!!!That was only last week.turn out that when I install the KudaJantan injectors...the mechanic didn't change the intake manifold gasket and didn't lock the bolts tigh enough.Now......???? New engine aledi....*sigh*

 

[Zoggee]

Originally posted by CAJ19@Dec 7 2004, 02:24 PM When I hit hard on the gas pedal, a very high hissing sound comes from the engine bay. Tried to check for loose air hose connections but all were in order. Even took out the intake manifold, still could not trace the source of sound. It happens only when the rev reaches >2500rpm. Issit normal for a 525 single vanos to sound like that when you rev hard???? Sifus, please help
huh...you took out the intake manifold by urself hah??? and you still asking question here....I guess you must be one heck of a D.I.Y khaki too.I dun think there's any vacum or hose leak la bro...better have ur mech to look at it.

 

[CAJ19]

In the states, you've got no choice but DIY. Here labour is cheap. In this case, mechanic ask to leave car for a week for trouble shooting. What the heck, tot its onlyvacuum hose leaking. Started stripping and finally the manifolds were out too. Verdict: can't find that damm snake!!! Sifu's, could it be the torque convertor??? h34r:

 

[sazli]

CAJ19,Your tires still available (225/55/16)?

 

[CAJ19]

yeap, still in cold room! Actually left it in my fren's shop for sale. PM me or call 012-3755537TAN.

 

[pussy]

the hissing sound can't be from your intake manifold..please take time to answer the questions below to know the problem.1.does your engine idle roughly ?2.did you check all your hoses leading into the intake manifold ?3. check your icv for leaks, sometimes the 'c' hose cracks or the plastic connector breaks.4. check your fan belts bearings.. maybe loose5. can be your alternator bearings.6. check your brake vacum hose for cracks or the non return valve7. your gearbox shudders.. - check your 'rubber bunion'- do a ATF flush, flush not drain- cahnge your atf filter- check your gearbox mountings, the small ones further to the back is most prone to breakage.. it last for one year or most.. let us know..regards.pussy

 

[erica34]

Originally posted by three28@Dec 7 2004, 03:30 PM...Check with e34 sifu's like bundy , blackcat and erica..
me just si fat... 5 minutes looking at bentley manual already pening liao... my simple solution to everything is send to workshop... doesn't always work... if fail, try again... still fail, try next workshop...

 

[CAJ19]

items 1-6 are all in order.Idling is smooth like babe's butt, but when engaged on drive position car shudders slightly. All hoses replaced new. New beltings. All undercarriage bushings replaced new. Belt tensioner- new. Waterpump- new.The only thing not done is the ATF flushing. Do you think Selvam can do this?

 

[ScottMcCavanaugh]

ok

When I hit hard on the gas pedal, a very high hissing sound comes from the engine bay. Tried to check for loose air hose connections but all were in order. Even took out the intake manifold, still could not trace the source of sound. It happens only when the rev reaches >2500rpm. Issit normal for a 525 single vanos to sound like that when you rev hard???? Sifus, please help

Great post. I'm just not completely sure that I'm understanding the depth to this.
Can anybody explain this out a little bit more?