So I've got a musical gremlin down inside my car - solved

[MMMEAT]

I thought I'd throw this out there for you guys..

There is a weird musical rattle that sounds like a tight wire bouncing off another "object" down inside the console/tunnel area of my 740. It only happens (or is audible) at low speeds, and seems especially prevalent when right at about 15-20mph and when turning and accelerating. I assume it's happening because of body flex and/or driveline stress/flex.

But it is incredibly difficult to pinpoint. We at first thought it was because of worn exhaust hangers..then I thought "AH HA!" and realized maybe it's the e brake cable, as it sounds like it is right there in that area, behind the handle. But applying the Ebrake while the noise is happening doesnt' seem to make any difference.

It is this really weird boiiinng sound with a rattle touch on it..very tough to describe. But it sometimes lasts for a couple seconds and sometimes for upwards of 5-10 seconds. Sometimes I think it's a loose rod or something down under the back seat, but then it sounds like it is right in the console/tunnel area. I can't find any heat shields or anything loose under there. Guibo is nice and clean and tight..drive wise, the car is going perfectly.

Any thoughts? Anybody ever heard something similar? Thanks!

[S1L1SC]

Loose change under the tunnel or the rear seat vents?

[MMMEAT]

Loose change under the tunnel or the rear seat vents?

No it's more of a mowowowboingboing than a ticktickrattlerattle.. lol

[JHluthier]

Maybe have someone else drive while you crawl around to narrow down the source?

Guibo is nice and clean and tight..drive wise, the car is going perfectly.

And I'm about to have the pleasure of crawling under to replace mine in the next day or two. The real fun part will be cutting through my exhaust and putting it back with butt clamps because the geniuses that did my custom exhaust chopped off the flanges and welded the whole thing up. My guibo looks like pulled pork and my seat turns into a massage chair over 1/4 throttle.

Is there supposed to be some kind of heat shield there? Seems like the proximity to the exhaust couldn't be helping the life of the thing.

[CroughtonE32]

Was just going to say, check the heat shield at the Cat Converter. If you can make the noise happen and it's vibrating there, just give it a little bend. But before you tear the entire car apart, I'd give a thought that almost every problem we have with E32's, from flickering lights, to broken sunroofs, leaking steering boxes, transmissions that won't shift, windows that crack on their own......................it always boils down to the "Mustard Relay". One day, when I was still working, I was scanning a patient, and the Magnet went down. In MRI terms, that would mean reschedule patients and call the MRI repair service from G.E. The last time that happened, I just walked out to the parking lot, opened my hood, took off the fuse box cover, and jiggled the Mustard Relay. Walked back into my diagnostic center and the magnet was fine. It's the fix for everything in life.

[MMMEAT]

Well I was just all excited on the way back from lunch, as my buddies had to go in to Walgreens and buy a couple things. I waited in the car, looked down into the hole left from the long-ago removed car phone in the console. I saw a few gum wrappers, and stuck my fingers way in there and finally worked an object. Presto! It was a spoon. Yeah a metal teaspoon..this HAS to be it!

So when my friends came back, one said "what are you doing with a spoon? Laughing hysterically I am all excited..time for the test. I was about to lay down a big bet with the others that this was IT.. One slow turn, no sound. Another slow acceleration, no sound. Woohoo! Then I have to do a U turn to get back onto the street..beyoingoyoyoingg..

Dammit, it's still there. Not the spoon..


So how do you tear apart the console? I don't even know where to start. It seems way too close to our ears to be under the body of the car..

[S1L1SC]

Maybe the knife and fork are in there as well?

[MMMEAT]

Was just going to say, check the heat shield at the Cat Converter. If you can make the noise happen and it's vibrating there, just give it a little bend. But before you tear the entire car apart, I'd give a thought that almost every problem we have with E32's, from flickering lights, to broken sunroofs, leaking steering boxes, transmissions that won't shift, windows that crack on their own......................it always boils down to the "Mustard Relay". One day, when I was still working, I was scanning a patient, and the Magnet went down. In MRI terms, that would mean reschedule patients and call the MRI repair service from G.E. The last time that happened, I just walked out to the parking lot, opened my hood, took off the fuse box cover, and jiggled the Mustard Relay. Walked back into my diagnostic center and the magnet was fine. It's the fix for everything in life.

Lol duly noted..Mustard Relay. In my notes on the iphone

[shogun]

Console removal see page 2 http://bmwe32.masscom.net/johan/dash...al_v1.1-1.html

[JHluthier]

If you disconnect your cluster DISCONNECT YOUR BATTERY FIRST. My srs system is fine, but since the srs light itself is considered an essential part of the system it will warning flash on you if the car's energized when you pull it.

Btw, anyone around Knoxville have an srs reset tool I could borrow for like 10 seconds?

[unity]

Odd, i've never had a problem pulling the cluster with battery hooked up. Now the airbag... thats an issue - but only if the key is turned with it disconnected, because that is when it does a self-test.

[shogun]

Btw, anyone around Knoxville have an srs reset tool I could borrow for like 10 seconds?

you need one like the ones I sold = SIR3 or BOA, but I have no more on stock, sold out. The others like Peake or the cheapo chinese made B800 do not work on E32 and cars built > 1994/5.
I only have 1 BOA here for myself and friends, but to send to TN is a bit far and costly.

[JHluthier]

you need one like the ones I sold = SIR3 or BOA, but I have no more on stock, sold out. The others like Peake or the cheapo chinese made B800 do not work on E32 and cars built > 1994/5.
I only have 1 BOA here for myself and friends, but to send to TN is a bit far and costly.

Yeah, I have the big round connector and know about the Peake, etc.

I seriously considered yours back when you had them, (what was it, only $40 plus ship for the cheaper one?) but just couldn't justify the price for a simple blinking light at the time.

Should have picked one up though. Probably could have sold it by now, and even if I hadn't I surely wouldn't feel bad about you making a couple ¥ considering how much you contribute to the community.

I don't think I've actually thanked you personally, but your site, what you contribute to the forums, and how active you remain in the online community, is beyond invaluable. While shogun is a great handle, from what I've seen you're nothing less than the true Tennō of the E32 world.

I guess that traditionally, general is a much more active role than "heavenly sovereign", so maybe shogun is just right, haha.

[MMMEAT]

Console removal see page 2 http://bmwe32.masscom.net/johan/dash...al_v1.1-1.html

Oh my..that is quite a process..I liked the quote at the end. "End of page, beginning of nightmares"..Umm, yeah!

[JHluthier]

Maybe try pulling just some of the lower pieces and glove box? You can pick up a bore scope that will connect with a smartphone(wifi is best) for really cheap these days. Have someone drive it while you prod around anything boinging.

If you pull the glove box you can easily change your cabin air filter while you're at it.

[MMMEAT]

Maybe try pulling just some of the lower pieces and glove box? You can pick up a bore scope that will connect with a smartphone(wifi is best) for really cheap these days. Have someone drive it while you prod around anything boinging.

If you pull the glove box you can easily change your cabin air filter while you're at it.

It's down in the console area between the seats..I once again got excited yesterday when I pulled the back cap (where the rear seat cig lighter is) off, tightened one of the screws holding the console down..I found the old phone connector was lying loose in there and thought maybe it was bouncing around. Also were a barrett for hair, a bunch of change, gum wrappers etc. I buttoned it all up and went for another test drive failure (although the console is now tighter at least)..shoot..

So I should have gone ahead and pulled the entire cover off the e brake handle. I believe I can just un screw the two big screws in the back of the console and then unscrew the one in the front of the cubby carrier box and this section will pop off and reveal stuff down around the brake handle and cables, right? It HAS to be down in there.

I quickly read through the instructions from the above link Shogun showed, but was a bit confused as to the ability to just undo the back portion..I don't need to get after the fore-sections..Yet.

[shogun]

it is all in the workshop manual, page 51-16/3 , removing and installing center console https://www.bmwtechinfo.com/repair/m...es/4810787.jpg

[MMMEAT]

OK then..so I removed the back seat last night and managed to find a couple things..first, a bracket for the battery tie down was just laying next to it. AH HA! Test drive..Nope.

And then a loose washer on the home made tie down assembly I'd made above the battery..test drive..nope

And then I tackled and shook and wiggled the center arm rest assembly above the back seat. Ah HA! There is a pair of plastic brackets on the bottom of this assembly, where the armrest pivots over the mounting point. One of them was loose. Ah HA! This has got to be it. Tightened screws (very hard to get at because of the angle though) Test drive..BoingityBoooing!!

Dammit.

So back into the trunk I go. The noise is definitely more pronounced now that the seat bottom is off, though. This is the good news. I'm starting to isolate it. But now it sounds a lot more "aft" in the cabin. So I'm back in the trunk and lift up the cover on the spare. The damn screw for the hold down for the tire is not tight. This is too easy..screw it down tight. Test Drive..DAMMIT BOINGoBoINGDingDong!....

Sigh..What in the Hell?? Where is this thing?


And yes, she was on the lift Sunday and I was under there grabbing and pulling every possible object/shield/exhaust component I could find..I'm going mad here..

[shogun]

Rear shock mounts lose?

[E32FAN]

My 1995 540 iA did exactly this in 2003, and it turned out to be caused by broken ceramic pieces rattling around inside the front muffler.

[JHluthier]

My 1995 540 iA did exactly this in 2003, and it turned out to be caused by broken ceramic pieces rattling around inside the front muffler.

Hell, that sounds fun.

[E32FAN]

Hell, that sounds fun.

I was in my car up on the hoist, revving the engine, and the tech was underneath listening and feeling for vibrations. He only found the cause when he pulled off the muffler and gave it a good shake! Rattle, rattle. These ceramic pieces were vibrating in a narrow resonance of the exhaust note. Makes sense, after all. In retrospect.

[MMMEAT]

I was in my car up on the hoist, revving the engine, and the tech was underneath listening and feeling for vibrations. He only found the cause when he pulled off the muffler and gave it a good shake! Rattle, rattle. These ceramic pieces were vibrating in a narrow resonance of the exhaust note. Makes sense, after all. In retrospect.

Hmm..this sounds interesting, but this noise of mine seems to have nothing to do with engine/exhaust pressure or RPMs. I have noticed one hill I always go down on my commute..as it's a 30mph zone, all downhill, it's constantly doing it down this 1/8th mile hill.. On level roads, it's only doing it upon acceleration, right through the 15-25mph zone and it goes away. Also sometimes on deceleration, but it's more about speed than it is about rpms.

It's not possible that it is my loose strut dust boots, is it?? I mean those things are all flopping around, but they really don't make any noise to speak of. This seems to be something down deep in the area of the guibo joint..but it all looks and feels strong down there when examining on the lift.

I got excited the other day when I thought I caught my muffler banging on the side of the lower black body trim so I shaved off a little bit of it..no dice..

[MMMEAT]

Update #7..

Well so my friendly helpful magical tech had the car on the lift last week and intstalled a few tired and stretched old exhaust hangers. Surely this was going to help, right!? Nope..

After getting my new brake master cylinder installed (one of the "diagonals" went out completely, ughh, there goes another 400 bucks) and he got to driving it again, we found that the car seems to definitely quit doing this boingy doingy when it is not "under power" . I tested it myself this morning on a hill that notoriously produces the sound. Yup, by gosh it goes away when just gliding with momentum. So he and his boss think it's the driveshaft center carrier. But it is of course buried up under a lot of exhaust equipment (ironic, right?) and needs to be dug into again. The boss mechanic seems to think that perhaps the carrier bearing got out of round or damaged just enough from years and years of sitting (with the weight of the driveshaft assembly on one or two bearing pins?) and when it's at a particular RPM, it is resonating a vibration up into the cabin. That certainly seems to be the location, too, where I hear it.

Now another question is..do I go ahead and spend the 900.00 plus for the entire new assembly in case a U joint is bad, or do I just try spending the 40.00 for a carrier and try it out (with another few hours labor cost too) and take my chances? Strangely, the mechanics don't seem to think it's an "urgent" problem, but (for now) just one that could go from irritating noise to outright problem in time..

[XAlt]

CSB causes all sorts of weird noises.