Hi, finally got the pictures of the back box on my 2007 xkr. Have pictures for you to view as you can see it joins up to the center box middle way in the car. Each pipe is 3 inches in diameter stainless steel. Just the other day the exhaust has lost a bit of its noise (growl). It had a very loud noise, louder than original xkr exhaust. I would say even louder than an xkrs (a real deep rumble). The sound seems to have been toned down a bit for some reason. I removed the F19 fuse to see if it would make a difference but it's still the same. On occasions I would have given it a bit of throttle when parked. This exhaust was fitted by the previous owner so Im not sure what make it is. All I know is that he got it in the U.K. Would I have damaged anything in the box? Does anyone have any answers to what It may be?

 

Pretty sure you have the same system as me

Elite RR XK/XKR Performance Rear Exhaust Box Quad Tips | eBay

Elite Xkr cat back... Sounds absolute awesome... Pulling fuse 19 has no effect...

Why it has become less loud I do not know... hope you figure it out asap, because it would be a pity not getting the full experience..)

 

Will have a look on there site. Yes the sound is amazing, cant know what happened

 

Fuse 19 would only work if you have the stock baffled exhaust where the baffles stay open when you pull the fuse. The aftermarket system you have does not have this feature .

 

Ok will put back fuse. Think it is elite box as I have picture and looks similar. Might give them a ring monday to see. Sounds pretty good at the moment but was much loader, mystery

 

The fiberglass noise deadening material may have come loose in the box and is creating a blockage.

I'm not 100% sure this is the problem but I had read about some Audi guys complaining about this with the Milltek cats back for their models when I was researching aftermarket exhausts.

 

If there is a blockage can it do any harm, seems to be working ok from both pipes, no bark though. Is there a fix. Looked last night and elite and milltek do a similar back box, whether it is one of theres.
Looked underneath again today and saw 1 small vent pipe on each side, above back box now tied up with holes blocked, Were these the valve pipes for factory box.

 

Yeah, those are probably the vacuum pipes for the active valves.

 

Another point, when your under the rear box of the car, legs facings out on yur right hand side look up, kind of behind bumper you c a lead like battery earth lead, says battery on lead. It is tightened on with a nut. Took rubber cover off it, all blue corrosion, cleaned and covered with protective Greece and put rubber back. Could b cause of some electric gremlins

 

That sounds like the grounding point for the fuel pump

 

[QUOTE=powerhouse;1000621]Another point, when your under the rear box of the car, legs facings out on yur right hand side look up, kind of behind bumper you c a lead like battery earth lead, says battery on lead. It is tightened on with a nut. Took rubber cover off it, all blue corrosion, cleaned and covered with protective Greece and put rubber back. Could b cause of some electric gremlins[/QUOTE

I noticed the other day that under the left side the same battery lead with a rubber cover. On my 2012 XKR this is the POSITIVE (+12V) terminal from the battery. If I look in the boot and remove the left hand grill to get to the battery terminal it is the same as under the car. I plan on hooking up my smart charger on this terminal from under the car . I would use a meter to test to make sure yours is not a ground wire but the +12V wire.

 

yes mine the same, as i said has a battery/starter sticker on it, mine all corroeded. Bet this is the cause of some starting or battery issues.

 

Well contacted elite and milltek and they can't confirm it's there box, maybe a copy.
Drove the car yesterday and the loud roar returned, today gone again, back to normal xkr sound.
Got under the car, checked system with no seal leaks, took off the rear box and not rattles, back on.
It's BAFFLING me, excuse the pun

 

Hohoho

It is odd, though. Maybe the problem is at the other end, i.e. in the cats or the centre boxes.

 

How do i know if there is cat problems, no rattles when idleing, done around 300 miles this last 2 days and plenty of passing out no power issues, shoe down, whine of charger and smile on my face. Hard to describe the noise i had, people compared it to an american muscle car, unreal loud, could hear nearly a mile away, that good, miss it bad.

 

This sounds like the system we are all after, I run with the fuse out all the time , I have mine on a switch but never turn it off, still not loud enough. Do you get a drone in the cabin??

 

no drone noise in cabin, mine has only one centre box, which has the wading inside removed, same as straight through