Author Topic: standard M42 stuff (Read 3959 times)

Belteshazzar · « **on:** January 18, 2008, 09:51:57 AM »

I've been living with my 318 for a couple weeks now, some observations;

a guy gets used to the power level fairly quickly. not nearly as maddening as I feared.

the exhaust sounds TERRIBLE. It all appears to be in decent shape, but just sounds like there's a baffle loose or rattly flexpipe or SOMEthing. It's got this buzz that makes me want to put it in neutral and cost anytime I can.
Funny thing is, my friend's 318ti sounds exactly the same way.

it idles like crap. it doesn't seem like a mechanical deal, like watching an old GM V6 shiver and shake. it's more like an ecu that has no idea what's going on.

Any common cures for this stuff?

tjts1 · « **Reply #1 on:** January 18, 2008, 10:02:03 AM »

Search:
Idle control valve
the mess under the intake
coil on plug
cleaning the intake

Belteshazzar · « **Reply #2 on:** January 18, 2008, 11:36:08 AM »

sounds pretty normal. Does the exhaust always sound this way?

tjts1 · « **Reply #3 on:** January 18, 2008, 11:49:44 AM »

Nah, my exhaust sounds like crap too. Its all rusted out on the inside.

kowalski · « **Reply #4 on:** January 18, 2008, 01:28:49 PM »

another common problem for a hunting idle is the afm. old springs in them, and word out contacts.

Belteshazzar · « **Reply #5 on:** January 21, 2008, 11:21:17 AM »

Quote from: tjts1;41379

Nah, my exhaust sounds like crap too. Its all rusted out on the inside.

do those flexible connections that are built into the factory header ever wear/get-loose? basically everything behind that on mine is new.

kowalski · « **Reply #6 on:** January 21, 2008, 12:21:22 PM »

Quote from: Belteshazzar;41469

do those flexible connections that are built into the factory header ever wear/get-loose? basically everything behind that on mine is new.

flexible connections?

D. Clay · « **Reply #7 on:** January 21, 2008, 01:27:31 PM »

The exhaust issue is usually loose baffles inside the rear muffler. The M42 is harder on exhaust than any car I have ever owned. Midas and the usual aftermarket mufflers last two years at best. I finally ponied up for the Eberspacher OEM muffler for $185 from bmaparts.com. Unfortunately it is at least twice as heavy as others. I've never had any luck with the one piece cat-backs.

Petebee · « **Reply #8 on:** January 22, 2008, 04:27:50 AM »

Quote from: D. Clay;41481

The exhaust issue is usually loose baffles inside the rear muffler. The M42 is harder on exhaust than any car I have ever owned. Midas and the usual aftermarket mufflers last two years at best. I finally ponied up for the Eberspacher OEM muffler for $185 from bmaparts.com. Unfortunately it is at least twice as heavy as others. I've never had any luck with the one piece cat-backs.

How did you attach this? Cut the one piece cat-back in front of the muffler and clamp the new muffler into the old section of pipe? Most after market cat-backs are quite expensive for these cars, and the Ansa on bmaparts looks pretty cheap.

D. Clay · « **Reply #9 on:** January 22, 2008, 10:25:34 AM »

I had it welded at a muffler shop for $30. I have the BMW clamp but it was impossible to get it to seal. Other people have told me they never had a problem with them. My problem is probably that I have heated and bent the exhaust for ground clearance. I never tried the ANSA but I have had one from BavAuto.com for $195 that lasted about two years and one from Midas that was welded on with a lifetime guarantee. I had it replaced twice (cheapy). I think a lot of cat backs are damaged in shipping. The metal is thin. I fixed a cat back once by pushing on it until it quit rattling and then drilled into the baffle a put a sheet metal screw in it. Again, some people look at me like I am crazy when I tell them how many rear mufflers I've had on the car. They buy a cat back from BMA and never have any problems.

Belteshazzar · « **Reply #10 on:** January 22, 2008, 11:50:16 AM »

Quote from: kowalski;41474

flexible connections?

the short acordian-looking thing that's built into the header before it merges into one pipe.

my muffler doesn't have any baffles to rattle, though that is the sort of sound I'm chasing.

haledj · « **Reply #11 on:** January 22, 2008, 12:31:10 PM »

Quote from: Belteshazzar;41525

the short acordian-looking thing that's built into the header before it merges into one pipe.
QUOTE]

:confused::confused::confused:

Belteshazzar · « **Reply #12 on:** January 22, 2008, 12:45:47 PM »

The factory header goes 4-2-1. Before it merges into one pipe, while it's still two, there's what appears to be a flex-joint built into each. It's not more than about two inches long.
Am I alone?

kowalski · « **Reply #13 on:** January 22, 2008, 06:31:11 PM »

Quote from: Belteshazzar;41529

The factory header goes 4-2-1. Before it merges into one pipe, while it's still two, there's what appears to be a flex-joint built into each. It's not more than about two inches long.
Am I alone?

yup. No accordion looking things on any m42 headers i've ever seen. post a pic