help with a noise

B6/7 S4/RS4
#1

When I turned my car on last night, it sounded like this. It is incredibly loud, and very rough, and when I popped the hood to take this video and look around, it was so loud that I could not pinpoint the location of the noise. Any ideas?!

https://vimeo.com/60946732

2008 B7 S4 with JHM s/c, piggies, magnaflow cat-back

Multiple tunes, though I don’t think we ever got it right, since I still get an occasional CEL on WOT

Last time I drove it, was yesterday, and I did a few hard pulls (typical on ramp stuff), but it did not sound like this.

Any ideas? What should I do? JHM isn’t close (3.5 hr drive), and I don’t have a good audi guy close by. Pull codes? take more videos?

#2

Definitely check for codes the audio is tough… What exactly is the noise that you don’t like. . Can you describe it?

Also get a good look at your belt to see if it’s okay.

#3

It’s SUPER loud, metallic, clacking, and the car seems to shake, but that’s maybe just me
I turned it off immediately, and am reluctant to start it up again, I’ll go check codes
My extremely uneducated guess is timing chain guide
What belt - the S/C belt?

#4

There’s a serp belt at the front of the engine to drive the accessories. A dead battery while driving is one of the symptoms I think.

#5

{he has a jhm supercharger so he will have their belt and pulleys. Could be a shredded belt thwacking on the various metal parts. Can make an epic noise.

#6

did the frequency of the sound change with engine speed?

#7

He just started it and turned it off

#8

Don’t know. I actually drove out of the driveway, heard it, turned the radio down, got out, thought “holy crap that’s loud” then turned around and pulled back into the garage, popped the hood, took the video, and turned it off.

#9

Just pulled the codes:

Address 01: Engine Labels: Redir Fail!
Part No SW: 8E2 910 560 HW: 8E2 907 560
Component: SC8+ V3JHM STG1G 0030
Revision: --H01— Serial number: XXXXXXXXXXXXXX
Coding: 0007711
Shop #: WSC 78643 024 403014

5 Faults Found:
17537 - Fuel Trim; Bank 2 (Mult): System too Rich
P1129 - 002 - Lower Limit Exceeded - Intermittent
Freeze Frame:
Fault Status: 00100010
Fault Priority: 0
Fault Frequency: 3
Mileage: 87744 km
Time Indication: 0

         Freeze Frame:
                RPM: 3277 /min
                Load: 30.2 %
                Speed: 124.0 km/h
                Temperature: 91.0∞C
                Temperature: 5.0∞C
                Absolute Pres.: 790.0 mbar
                Voltage: 13.843 V

16684 - Random/Multiple Cylinder Misfire Detected
P0300 - 001 - Upper Limit Exceeded - Intermittent
Freeze Frame:
Fault Status: 00100001
Fault Priority: 0
Fault Frequency: 2
Mileage: 88792 km
Time Indication: 0

         Freeze Frame:
                RPM: 2749 /min
                Load: 44.7 %
                Speed: 104.0 km/h
                Temperature: 91.0∞C
                Temperature: 21.0∞C
                Absolute Pres.: 1010.0 mbar
                Voltage: 13.589 V

16688 - Cylinder 4: Misfire Detected
P0304 - 001 - Upper Limit Exceeded - Intermittent
Freeze Frame:
Fault Status: 00100001
Fault Priority: 0
Fault Frequency: 2
Mileage: 88792 km
Time Indication: 0

         Freeze Frame:
                RPM: 2749 /min
                Load: 44.7 %
                Speed: 104.0 km/h
                Temperature: 91.0∞C
                Temperature: 21.0∞C
                Absolute Pres.: 1010.0 mbar
                Voltage: 13.589 V

16687 - Cylinder 3: Misfire Detected
P0303 - 001 - Upper Limit Exceeded - Intermittent
Freeze Frame:
Fault Status: 00100001
Fault Priority: 0
Fault Frequency: 2
Mileage: 88792 km
Time Indication: 0

         Freeze Frame:
                RPM: 2749 /min
                Load: 44.7 %
                Speed: 104.0 km/h
                Temperature: 91.0∞C
                Temperature: 21.0∞C
                Absolute Pres.: 1010.0 mbar
                Voltage: 13.589 V

17535 - Fuel Trim; Bank 1 (Mult): System too Rich
P1127 - 002 - Lower Limit Exceeded - Intermittent
Freeze Frame:
Fault Status: 00100010
Fault Priority: 0
Fault Frequency: 2
Mileage: 88797 km
Time Indication: 0

         Freeze Frame:
                RPM: 3286 /min
                Load: 30.6 %
                Speed: 124.0 km/h
                Temperature: 91.0∞C
                Temperature: 5.0∞C
                Absolute Pres.: 790.0 mbar
                Voltage: 13.589 V

Readiness: 0000 0001

#10

Just saw the missfires all came at the same point in time and load. I would clear all tje above and go from there. Those codes defd8nitly are not from what ever happened with your car recently

Take a look and see if your belt is still on the car. Or if anythi g is up in tue front

#11

Good observation, Engine fault codes came 3000 km ago.
JHM Serp belt looks solid (when viewed from above with a flashlight)
So you think I should clear all the codes…and then what?

#12

That noise sounds serious. Look for any obstructions in the belt path. It would help to know if it was running rough. Chances are good if it was a chain issue you would have codes for the adjusteres

Lookunder tue car where the belt drive is see if anything is hangng down

#13

It felt very rough when I pulled out of the garage, for whatever that’s worth…

Hmmm, don’t have a good jack or stands to get the front up and take off the underbelly pan to look at it from underneath.

I guess I’m trying to decide, with my non-existant mechanical skills/knowledge: Do I take my chances with my local Audi guy, who’s not every good but only 5 miles away? Or do I take it to JHM, and should I have it towed to either?

#14

Correction - my records were wrong, Oil consumption appears to be ok

#15

If it were me, I would tow it to JHM. I made the mistake of driving my car to the dealership, thinking it was running rough from bad coil packs. Turned out to be a cam adjuster and guide, lost 30 valves in the process. Not trying to scare you but I learned the hard way.

#16

Underway - I called 15 towing companies: local to me, and local to JHM. Turns out Keaton made an arrangement for a better price than I could. Car will leave today. I’ll let you all know how it turns out.

http://i.imgur.com/GOyZxTt.jpg

I sure wish my local mechanic was more performance oriented!

#17

Good choice on towing immediately to a good shop and good luck. I hope it’s something relatively simple.

#18

Whew, front serp belt bearings were the cause. It sounded like all 8 cylinders were exploding, glad all is good.

#19

Glad to hear it. Well worth the tow for such a quick diagnosis!

#20

Sorry I just saw this, but yea I was about to say I’d heavily bet on that being the front serp belt.

If I recall, you were one of the earlier s/c guys, and they have changed their idler pulley components since first install. . . . I had an idler disintegrate on me and shred the belt. Wasn’t a pretty sight and scared the shit of me when it happened as I was ripping through 1-2. Battery light popped on and had some terrible clunking noises. New idler design are free of this issue though and been good ever since. JHM said that was the first time they’d ever see it happen lol.