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WTF!!??
I recently did all the rubber and gaskets on my 94 540i intake manifold. All my idle and codes problems are gone!
Today, Im running down the road and this saxophone sound comes from the engine WHEN I LET OFF THE GAS. (MAX VACUUM RIGHT?). When I get on the accelerator...no sax sound.
Car does the same thing when parked; sound comes from engine.
AC OFF; Heater OFF; No codes; Idle is smoothest ever since Ive had the car.
explain the idle problems you had before.
crankcase ventilation plate. On the cars i've heard it on its worse when coasting down as you describe and sometimes when the engine is cold at idle also. Indicates bad crankcase ventilation valve or plate.
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Originally Posted by MBXB
Are you sure the sax sound does come from the engine and not from the charcoal canister?Quote:
Originally Posted by MBXB
In my car, it has openings on the bottom and its possible to get resonance from the air passing through into the engine if the evaporative purge valve is stuck open. This was an issue with my car very recently.
Sound is definitely from the engine.
PCV plate was replaced along with:
All vacuum hoses,
All fuel lines,
Intake manifold gaskets,
PCV plate gaskets
Throttle body gasket;
Fuel injector Orings
New PCV Pipe Orings and Clip
ICV cleaned and Orings on both ends replaced;
new clamps everywhere
new rubber plugs on the PCV plate
Fuel Injectors refurbed and spc'd
New Orings on injectors
how is the charcoal purge valve after all?Quote:
Originally Posted by MBXB
forgot the intake valley pan gasket.
Quote:
Originally Posted by MBXB
:), pull the dipstick out and run it with it out of the hole a little ways and see if the noise quits on coast down.. that will confirm that its vacum in the engine causing it... it won't pinpoint it but it will confirm it. Then you may want to disconnect the line going to the charcoal canister and plug it off just to check that as well ,as Rustam says. I still suspect its your new pcv plate though...
Quote:
Originally Posted by MBXB
I didn't mess with that at all.
Where is the line that goes to the canister?
Quote:
Originally Posted by Bill R.
You can use this link:Quote:
Originally Posted by MBXB
http://realoem.com/bmw/showparts.do?...83&hg=13&fg=15
The purge valve is "number 1". The cylinder right above it is the charcoal canister.
If you find that it does not work it's easy to clean avoiding $.
through the bottom of the throttle body
Quote:
Originally Posted by MBXB
that's coolent down there
Quote:
Originally Posted by 632 Regal
i just did a 740 that pulling the oil cap off while running made a sound like popping the top on a beer can SSSSSHICK, those plates suck
Don't know if this makes a difference or not, but another detail
I forgot to mention is that this sound only occurs after I've run a few miles, when the engine is well into operating range, and over 45 mph.
After that, I can replicate it parked or moving.
sounds like a vakum leak to me, did you check rubber hoses and that gasket inder the plastik carburetor thing?
Quote:
Originally Posted by MBXB
I replaced all rubber and gaskets.
Quote:
Originally Posted by Bleeding_Knuckles
how bout #2?
http://www.realoem.com/bmw/diagrams/d/h/4.png
I didn't even get that far down. Damn, I hope that's not it.
Quote:
Originally Posted by 632 Regal
.Quote:
Originally Posted by MBXB
that's coolent under there
Quote:
Originally Posted by 632 Regal
I didn't see any sign of leakage when I had the intake manifold out, so I guess Im good there.
Quote:
Originally Posted by winfred
In case of my car it is on passenger side under the water tank.
http://www.realoem.com/bmw/showparts...84&hg=16&fg=10
Here a pic from my parts 750, at the left you see the round black cannister
http://img6.imageshack.us/my.php?image=bmw11261fd.jpg
Just found another pics from another 750 in my yard. here you can see it better
http://bmwe32.student.utwente.nl/shogun/DSC00005.JPG
Do you have an idea where number 6 leads?Quote:
Originally Posted by shogun
this one appears to be unventilated type.Quote:
Originally Posted by shogun
do you know where the pipe at the side with the cap leads?
Any chance the pipe that runs under the manifold to the rear cover fell out? it can be tricky to get it all the way telescoped out and it can slip out later.
O ring could be sloppy, or the intake gasket popped out and is singing to you now.
Quote:
Originally Posted by joshua43214
And the winners are: joshua and 632Regal!
Good call guys.
I did the soapy water thing and couldn't locate any leaks.
I was ready to start ripping out the intake manifold and check for misaligned gaskets.
I decided to go over everything again and using a long screwdriver, tapped the PCV Pipe towards the firewall. It moved about 1/4 inch and stopped. Mother*****r!
Restarted the car and no sound. The O-ring must not have seated properly.
That entire PCV plate + pipe combination is one bonehead design.
great, glad you got it fixed.