Sound protection cap 11611435459

[Zchild]

Took my bimmer to the shop to get some cooling work completed and when I picked it up my vehicle had began producing a new sound that sounds like an exhaust issue, however after going to a number of muffler shops and getting told that my manifolds need replacing, my EGR valve was damaged and my exhaust needs replacement I thought I would simply take a look under the hood and low and behold my engine cover or Sound Protection Cap is freakin missing which means it was never replaced after the cooling repairs... Which makes me wonder is the new strange sound because the Sound Protection Cap is missing from my motor and the engine sounds are not being suppressed by the Engine Acoustics item designed to muffle engine noise in the cabin... Please let me know your thoughts as well as how much sound the Sound Protection Cap generates to the vehicle... Thanks in advance!

[edjack]

Go back to the shop and demand the cover!

Don't go there again!

[Zchild]

They value me as a customer and given the fact that I've dropped a ton of money with them they are replacing it free of charge... I spent almost $1,000.00 on coolant repairs when they misplaced or lost my engine cover...

[geargrinder]

The 'beauty cover' has very little impact on in-cabin noise IMO. I know it has that insulation on the top of it but it really doesn't do much for that.

By the way, it is NOT "EGR". EGR is a technology that's been obsolete on gas engines since the late 1970's / early 80's or so. If your mechanic calls it "EGR" then he's an unqualified incompetent and should never be used again.
What you mean to say is "Secondary Air Injection" system or "SAI" (often referred to as "SAP" also which literally is for "Secondary Air Pump" but very often casually just used to indicate "the whole dang system")
EGR and SAI are essentially polar OPPOSITES. EGR puts exhaust gas into the clean intake air, while SAI puts clean air into the exhaust manifolds.

Now - for a ticking noise - If the SAI pipes are not seated properly, or, the valve is malfunctioning and/or the plastic pipes are broken, you can get indeed all kinda noise. Very very unlikely your manifolds need replacing.

The SAI pipes seat from the front of the engine into each cylinder head into the exhaust passages. Its not that difficult to mis-install them so they don't meet up in the hole and then exhaust gas can come out the front and make a fair bit of noise (can sound much like a good old cracked exhaust manifold on a Ferd Pickitup truck or whatever would do... tickety-tick or sometimes worse and actual loud exhaust noise on WOT... )

If the cooling system guys pulled those pipes to do the cooling job, then they probably just didn't get them back in exactly right.
Its a bit of a tricky blind job as you can't see the port you are trying to stick the little tube into, and I would NOT condemn them for a little mistake like that as long as they fix it for free of course... it is for sure possible for to bolt up from the front and "look good" but not be actually in place, so is an 'understandable minor mistake' in my book.

[Zchild]

Thanks for the update; I was always sure it wasn't the EGR which is what a muffler shop stated it heard the sound coming from or Intake manifolds which is what yet another shop stated (only wanting $5,000) to fix replace them. Your response sounds more plausible as the sound began directly after the replacement of the water pump, several pulley's and the thermostat because the vehicle briefly overheated. The sound is a pronounced rattle under acceleration only, it subsides at any and all cruising speeds even in low gear. The heavier the acceleration the more pronounced the sound... I will take it to a BMW specialty shop and suggest they look into the SIA pipe seating. Thanks!

[RuskiE39]

When I had my 335i I had just finished up replacing the valve cover gasket and drove it without the engine cover.. MAN was it LOUD. I actually stopped and turned around because it was ticking loud and making strange noises. Lo and behold, it's very normal and when I put the covers back on it was nice and quiet. Not sure if its the same with the 540 but it could be..

[geargrinder]

Naw. The 540 doesn't sound that much diff't w/ it off.

- - - Updated - - -

Thanks for the update; I was always sure it wasn't the EGR which is what a muffler shop stated it heard the sound coming from or Intake manifolds which is what yet another shop stated (only wanting $5,000) to fix replace them. Your response sounds more plausible as the sound began directly after the replacement of the water pump, several pulley's and the thermostat because the vehicle briefly overheated. The sound is a pronounced rattle under acceleration only, it subsides at any and all cruising speeds even in low gear. The heavier the acceleration the more pronounced the sound... I will take it to a BMW specialty shop and suggest they look into the SIA pipe seating. Thanks!

Yeah, that sounds very likely it could be the Secondary Air pipe ever so slightly mis-aligned. I mean could be something else too, but given that the 'layman shops' you went to thought it was an exhaust leak, then I'd look at this as the water-pump-job + exhaust-leak-type-noise really points this way.

Below is a picture of it from Pelican, showing how hidden the end bolts and points are.

[Zchild]

You da man; thanks for the photos; now I'm at least armed with some knowledge and understanding concerning the possible issue... The car went into the shop sounding awesome and came out sounding like a pick-up truck overnight and missing the engine cover to top it off... I'm going over to my friends a Vortex Motorsports, their a German sports car specialist shop armed with the information provided and get this sorted PDQ; thanks again!

[lostinstx]

Just purchased a used 2003 540i M-Sport. The sound cover cap, 11611435459, is missing 2 of the 4 black "plugs" on the top. Does any know what the part number is for these?