04-06-2018, 07:37 PM | #1 |
Lieutenant
589
Rep 526
Posts |
MPE rattlings at cold start, driving around, and reverse
Recently bought a used 2015 M4 and I didn't know this until the day I came to pick it up but there's an MPE on it! It sounds great but I noticed on cold start and sometimes when driving around and reverse, it'll rattle. I've done some research and some people say it's the butterfly valve. Can anyone confirm from this video below. The rattling occurs right at the beginning and around the 23 second mark. Password is F82.
Also, the AC on the car doesn't work. It was fine when I test drove the car two weeks ago but when I ran it today, nothing but hot air. Seems like this is a known issue. Last edited by r0wr; 04-06-2018 at 07:45 PM.. |
04-06-2018, 09:56 PM | #2 |
Captain
554
Rep 908
Posts |
Your video is private and can not be viewed.
Start by checking the screws that secure the tips and ensure they are tight. I thought mine were tight at first but it turned out that 1 of them actually needed at least another turn. That resolved my vibration when I first got my MPE. If not the tips than it could be a bad part on the valves, exhaust hangers with a loose bolt/nut, a bad hanger, a loose heat shield, something touching the heat shield, the ebrake line rattling against the drive shaft (if your car did not already come with it fixed), cracked MPE, or something else. Could be something easy to fix or something that requires help. Good luck!
__________________
|
Appreciate
0
|
04-06-2018, 10:40 PM | #3 | |
Lieutenant
589
Rep 526
Posts |
Quote:
I appreciate your response. The password is F82. |
|
Appreciate
0
|
04-07-2018, 09:15 AM | #4 |
#LSBM3
1420
Rep 1,973
Posts
Drives: 2016 BMW M3
Join Date: Feb 2015
Location: Oregon / Florida
iTrader: (4)
Garage List 1984 BMW R65 [0.00]
2020 Ford F-150 XLT ... [0.00] 2003 Mitsubishi Evo ... [0.00] 2016 M3 Competition ... [10.00] |
I was able to view your video using the password you provided. Thanks for sharing. Watched it a couple times, especially the very first part. You can definitely hear the sound you are talking about. My first thoughts are...
1) Doubt it's this, but hold down the license plate and see if it stops. Could just be a light vibration from the frequency of the exhaust note at very low RPM's. 2) Check the MPE tips. Generally below 2000 RPM's most will experience a slight rattle coming from the MPE. This is usually due to a screw that just needs tightening. Here's a helpful link If the issue still persists, I'd get the car up on a lift and look for any areas were the exhaust may be touching a heat-shield or something similar.
__________________
/// M3 |
Appreciate
0
|
04-07-2018, 05:33 PM | #5 | |
Lieutenant
589
Rep 526
Posts |
Quote:
|
|
Appreciate
0
|
04-07-2018, 06:00 PM | #6 |
Second Lieutenant
98
Rep 233
Posts |
I've replaced an MPE muffler for this exact noise, under warranty. Only did it under cold start, VERY loud. I swapped out the Ti tips first, but it changed nothing. After that, had the green light to replace it under warranty.
|
Appreciate
0
|
04-07-2018, 09:42 PM | #7 |
Major
581
Rep 1,055
Posts |
I had the same noise on mine. Check the sides of the muffler can to see if there are hairline cracks on the welds where the pipes enter the can. My exhaust was replaced under warranty because of the cracks and the valves were stuck.
|
Appreciate
0
|
04-10-2018, 07:38 PM | #8 |
Lieutenant
589
Rep 526
Posts |
So I brought it into the dealership under warranty and they found 2 cracks on the muffler. It is being replaced in full. I also asked for the emblems on the seats to be replaced as mines were cracked and they did.
I tried to ask if I could pay the difference for CF tips and he said no haha. |
Appreciate
0
|
04-10-2018, 09:39 PM | #9 | |
#LSBM3
1420
Rep 1,973
Posts
Drives: 2016 BMW M3
Join Date: Feb 2015
Location: Oregon / Florida
iTrader: (4)
Garage List 1984 BMW R65 [0.00]
2020 Ford F-150 XLT ... [0.00] 2003 Mitsubishi Evo ... [0.00] 2016 M3 Competition ... [10.00] |
Quote:
Nice! That's great that they replaced it.
__________________
/// M3 |
|
Appreciate
0
|
04-11-2018, 10:48 PM | #15 |
Lieutenant
589
Rep 526
Posts |
|
Appreciate
0
|
04-12-2018, 09:15 PM | #16 |
Colonel
978
Rep 2,069
Posts |
An all too common problem. I recently acquired an MPE that had suffered cracking to the silencer sidewall - Common, as it's thin & the pipe joints coming out on either side are the only means of supporting the whole thing.
Although the cracks had been repaired, the 'rattling tin can' sound was still a problem, despite there now being no cracks. No receipt for the MPE, so had a local fabricator do this for me... Now there's no flex with the out pipes - And the rattle has been completely eliminated Happy days & £100 to do...
__________________
/// BM3 + M-Power ///
|
Appreciate
4
|
04-12-2018, 11:28 PM | #17 | |
Lieutenant
589
Rep 526
Posts |
Quote:
Nice, I'll be sure to note this next time when my new MPE breaks in like two years! Just received car. I wasn't able to test a true cold start but the rattling is gone at all RPMs. Will test a true cold start tomorrow morning to see if it rattles. |
|
Appreciate
0
|
04-14-2018, 08:35 PM | #18 |
Colonel
1883
Rep 2,924
Posts |
I have same issues with my MPE. Going to dealer soon and have them check it out !!!
__________________
Currently: '24 Mercedes G63 | '24 Porsche GT3 RS | '24 Volkswagen GTI
Previous BMWs: 340i, 740i, 745Li, M3, M4 Previous Others: Audi, Ducati, Honda, Infiniti, Land Rover, Mercedes-Benz, MINI, Mitsubishi, Porsche, Toyota, Volkswagen |
Appreciate
0
|
05-18-2018, 09:50 AM | #20 |
Major
581
Rep 1,055
Posts |
|
Appreciate
0
|
05-18-2018, 11:31 AM | #21 |
Banned
2056
Rep 1,984
Posts |
|
Appreciate
0
|
05-18-2018, 12:01 PM | #22 | |
Private First Class
112
Rep 103
Posts |
Quote:
It's been tampered so dealer can't do anything. Very unfortunate. I'm gonna put DP and Midpipes combo. Hoping the rattles won't be noticeable. |
|
Appreciate
0
|
Post Reply |
Bookmarks |
|
|