Hi everyone
Earlier on this year I decided to remove the cats and the secondary air system, which you all know robs the car of power. I sent it to an "expert" as I don't have the time to do it myself. I also installed Wagner intercoolers and the car is running like a bullet. I have one issue. When I'm driving it hard, no smoke blows out of the exhaust. When I drive it sedately ie 15-20% of max throttle, then lift off the throttle completely, I get quite a bit of smoke, that smells really strongly of petrol, coming out of the exhausts. if I blip the throttle, it goes away. I did fit a box from an electronic guy that usually sorts the problem out as it fools the computer into thinking that the flow through the cats is normal. Hasn't worked. Have any of you heard of this and do you know what I can do. The VCDS log does show that bank 1 and 2 are running rich.
Thanks guys. I hope i can sort it out because it looks so lame when an RS6 blows smoke!!
Problems after removing cats
Problems after removing cats
Viper'd, QTP exhaust valves, Wagner'd, dogged(no cats!)
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Mr Footlong
- Cruising
- Posts: 4331
- Joined: Thu Nov 10, 2011 12:07 pm
Re: Problems after removing cats
Did you even bother to remap the car??????????????????????
If not then cowboy-tastic job right there. Need more information but it all sounds a little bodge-like for my tastes. Electronic trickery box??? "shudder".
If not then cowboy-tastic job right there. Need more information but it all sounds a little bodge-like for my tastes. Electronic trickery box??? "shudder".
Current:
23' C8 RS6 Vorsprung - 23' RS E-Tron GT Carbon Vorsprung
Gone:
"Brutus"- C5 RS6 Avant - MRC stage 2 - Milltek non-res + 100 cell cats - Wagner ICs - PSS9 - H&R ARBs - OZ Superturismo LM - C6 Custom brakes - HD RNS-E - Various other bits - 555PS/832Nm
"Taz"- C7 RS6 - MRC stage 2 745PS/1095Nm
12' Cayenne Turbo, B7 RS4, S3, Cupra R, XJR, EVO VII, STI8,5,2&WRX, 106 GTI&XSI, other crap.
23' C8 RS6 Vorsprung - 23' RS E-Tron GT Carbon Vorsprung
Gone:
"Brutus"- C5 RS6 Avant - MRC stage 2 - Milltek non-res + 100 cell cats - Wagner ICs - PSS9 - H&R ARBs - OZ Superturismo LM - C6 Custom brakes - HD RNS-E - Various other bits - 555PS/832Nm
"Taz"- C7 RS6 - MRC stage 2 745PS/1095Nm
12' Cayenne Turbo, B7 RS4, S3, Cupra R, XJR, EVO VII, STI8,5,2&WRX, 106 GTI&XSI, other crap.
Re: Problems after removing cats
shudder +1. Removing cats with no map is pointless.
Did you block off the SAI ports after deleting? Sounds like you've got a massive air leak.
Might help if you posted the codes you got.
Did you block off the SAI ports after deleting? Sounds like you've got a massive air leak.
Might help if you posted the codes you got.
Daytona RS6 C5 Avant. Viper'd, Billies, Waggers, MTM box brain, C6 stoppers, xcarlink, R8 coolant cap (woohoo)
///M3 E46 | XC90 (V8, natch) | Passat GTE | RR Classic V8 flapper
"The major difference between a thing that might go wrong and a thing that cannot possibly go wrong is that when a thing that cannot possibly go wrong goes wrong it usually turns out to be impossible to get at and repair."
///M3 E46 | XC90 (V8, natch) | Passat GTE | RR Classic V8 flapper
"The major difference between a thing that might go wrong and a thing that cannot possibly go wrong is that when a thing that cannot possibly go wrong goes wrong it usually turns out to be impossible to get at and repair."
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Mr Footlong
- Cruising
- Posts: 4331
- Joined: Thu Nov 10, 2011 12:07 pm
Re: Problems after removing cats
The SAI robs the car of power? I just thought people took it off as it annoyed them. Never looked in to it as mine works and I like the noise it makes 
. Shopp?
. Shopp?Current:
23' C8 RS6 Vorsprung - 23' RS E-Tron GT Carbon Vorsprung
Gone:
"Brutus"- C5 RS6 Avant - MRC stage 2 - Milltek non-res + 100 cell cats - Wagner ICs - PSS9 - H&R ARBs - OZ Superturismo LM - C6 Custom brakes - HD RNS-E - Various other bits - 555PS/832Nm
"Taz"- C7 RS6 - MRC stage 2 745PS/1095Nm
12' Cayenne Turbo, B7 RS4, S3, Cupra R, XJR, EVO VII, STI8,5,2&WRX, 106 GTI&XSI, other crap.
23' C8 RS6 Vorsprung - 23' RS E-Tron GT Carbon Vorsprung
Gone:
"Brutus"- C5 RS6 Avant - MRC stage 2 - Milltek non-res + 100 cell cats - Wagner ICs - PSS9 - H&R ARBs - OZ Superturismo LM - C6 Custom brakes - HD RNS-E - Various other bits - 555PS/832Nm
"Taz"- C7 RS6 - MRC stage 2 745PS/1095Nm
12' Cayenne Turbo, B7 RS4, S3, Cupra R, XJR, EVO VII, STI8,5,2&WRX, 106 GTI&XSI, other crap.
Re: Problems after removing cats
No, doesn't rob the car of power. Only comes on when the engine is warming up. The only reason to delete it is if it has failed and you don't want to cough up for a new one since it's only for emissions.
Problem is, if you don't delete it properly (blanking off plates and mapped out) then you will have the check engine light on the dash which could be hiding other faults. At worst you will be letting unmetered air in.
Problem is, if you don't delete it properly (blanking off plates and mapped out) then you will have the check engine light on the dash which could be hiding other faults. At worst you will be letting unmetered air in.
Daytona RS6 C5 Avant. Viper'd, Billies, Waggers, MTM box brain, C6 stoppers, xcarlink, R8 coolant cap (woohoo)
///M3 E46 | XC90 (V8, natch) | Passat GTE | RR Classic V8 flapper
"The major difference between a thing that might go wrong and a thing that cannot possibly go wrong is that when a thing that cannot possibly go wrong goes wrong it usually turns out to be impossible to get at and repair."
///M3 E46 | XC90 (V8, natch) | Passat GTE | RR Classic V8 flapper
"The major difference between a thing that might go wrong and a thing that cannot possibly go wrong is that when a thing that cannot possibly go wrong goes wrong it usually turns out to be impossible to get at and repair."
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BillTheButcher
- 4th Gear
- Posts: 537
- Joined: Mon Feb 15, 2010 4:06 pm
Re: Problems after removing cats
Aggro65 wrote:I did fit a box from an electronic guy that usually sorts the problem out as it fools the computer into thinking that the flow through the cats is normal.
This sounds like a very bad idea.
Re: Problems after removing cats
Oh dear. OP, dif you check this site out before going getting it done?
Also, which 'EXPERT'?
Also, which 'EXPERT'?
previous- Pug 205 gti, 306 gti, 309 gti Goodwood.
Audi S3, S4 V8 avant.
Porsche Macan Turbo.
Gone but NEVER forgotten - C5 RS6 Misano red avant.
Now - Empty garage
If you don't know where you're going, any road will take you there!
Audi S3, S4 V8 avant.
Porsche Macan Turbo.
Gone but NEVER forgotten - C5 RS6 Misano red avant.
Now - Empty garage
If you don't know where you're going, any road will take you there!
Re: Problems after removing cats
1) FON
2) Removes Cats, and car goes to the dogs!
3) Get it into MRC or Unit 20 to unscramble the mess your "Expert" has got you into.
4) With proper report on what's been done demand money back from "Expert" - nb: "ex= has been; "spert"= drip under pressure
5) Enjoy your new car
6) Rule 1, or it's a myth!
Dave
2) Removes Cats, and car goes to the dogs!
3) Get it into MRC or Unit 20 to unscramble the mess your "Expert" has got you into.
4) With proper report on what's been done demand money back from "Expert" - nb: "ex= has been; "spert"= drip under pressure
5) Enjoy your new car
6) Rule 1, or it's a myth!
Dave
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Mr Footlong
- Cruising
- Posts: 4331
- Joined: Thu Nov 10, 2011 12:07 pm
Re: Problems after removing cats
Cheers for the confirmation Shopp. I knew all about the emissions part but didn't think for a second that it affected power, hence me asking you for confirmation 
Glad I am not the only one that thinks that this car is a pig's abortion in its current state of "tune" to be perfectly honest. Where in the country are you Aggro65?
Glad I am not the only one that thinks that this car is a pig's abortion in its current state of "tune" to be perfectly honest. Where in the country are you Aggro65?
Current:
23' C8 RS6 Vorsprung - 23' RS E-Tron GT Carbon Vorsprung
Gone:
"Brutus"- C5 RS6 Avant - MRC stage 2 - Milltek non-res + 100 cell cats - Wagner ICs - PSS9 - H&R ARBs - OZ Superturismo LM - C6 Custom brakes - HD RNS-E - Various other bits - 555PS/832Nm
"Taz"- C7 RS6 - MRC stage 2 745PS/1095Nm
12' Cayenne Turbo, B7 RS4, S3, Cupra R, XJR, EVO VII, STI8,5,2&WRX, 106 GTI&XSI, other crap.
23' C8 RS6 Vorsprung - 23' RS E-Tron GT Carbon Vorsprung
Gone:
"Brutus"- C5 RS6 Avant - MRC stage 2 - Milltek non-res + 100 cell cats - Wagner ICs - PSS9 - H&R ARBs - OZ Superturismo LM - C6 Custom brakes - HD RNS-E - Various other bits - 555PS/832Nm
"Taz"- C7 RS6 - MRC stage 2 745PS/1095Nm
12' Cayenne Turbo, B7 RS4, S3, Cupra R, XJR, EVO VII, STI8,5,2&WRX, 106 GTI&XSI, other crap.
Re: Problems after removing cats
Get rid of that and have it mapped in a proper place and odds are things will be fine. They'll do a vac check as well to see if there's any air leaks.Aggro65 wrote: I did fit a box from an electronic guy that usually sorts the problem out as it fools the computer into thinking that the flow through the cats is normal.
B7 RS4 saloon Misano red, comfy seats, JHM tune & JHM full exhaust with cats and resonators - gone.
C5 RS6 Avant Daytona/Cognac - gone.
981 Cayman GTS Gray/Orange.
My youtube
C5 RS6 Avant Daytona/Cognac - gone.
981 Cayman GTS Gray/Orange.
My youtube
Re: Problems after removing cats
I think you'll find MRC coded yours out, unless you asked them not to. Double check with Doug but I'm sure he told meMr Footlong wrote:The SAI robs the car of power? I just thought people took it off as it annoyed them. Never looked in to it as mine works and I like the noise it makes
he coded mine out so I'm guessing he would have yours too, although I think I can hear mine too, odd.
2009 Audi RS 6 Saloon V10 - 420mm Ceramics, Keyless, Soft Close, Adaptive Cruise, Glass Sunroof, Blinds, Twin Pane & UV, Freeview & DAB, High Beam Assist, MTM bits, Audi Exclusive Bits, MRC, Milltek, GYEF1 ASY2's, Bluetooth streaming music to AMI mod - 753PS, 1021 NM
2016 Audi S3 Saloon S-Tronic, Sepang, B&O, Tech Pack w/connect, 19" 5 Arm Wing Alloys, Comfort Pack, LED Light Pack - Company Car
1995 Audi A8 4.2 V8 quattro Sport
2016 Audi S3 Saloon S-Tronic, Sepang, B&O, Tech Pack w/connect, 19" 5 Arm Wing Alloys, Comfort Pack, LED Light Pack - Company Car
1995 Audi A8 4.2 V8 quattro Sport
-
Mr Footlong
- Cruising
- Posts: 4331
- Joined: Thu Nov 10, 2011 12:07 pm
Re: Problems after removing cats
Mine does the spinning up noise etc etc. Don't care if it is coded out or not, doesn't cause me any issues regardless.
Current:
23' C8 RS6 Vorsprung - 23' RS E-Tron GT Carbon Vorsprung
Gone:
"Brutus"- C5 RS6 Avant - MRC stage 2 - Milltek non-res + 100 cell cats - Wagner ICs - PSS9 - H&R ARBs - OZ Superturismo LM - C6 Custom brakes - HD RNS-E - Various other bits - 555PS/832Nm
"Taz"- C7 RS6 - MRC stage 2 745PS/1095Nm
12' Cayenne Turbo, B7 RS4, S3, Cupra R, XJR, EVO VII, STI8,5,2&WRX, 106 GTI&XSI, other crap.
23' C8 RS6 Vorsprung - 23' RS E-Tron GT Carbon Vorsprung
Gone:
"Brutus"- C5 RS6 Avant - MRC stage 2 - Milltek non-res + 100 cell cats - Wagner ICs - PSS9 - H&R ARBs - OZ Superturismo LM - C6 Custom brakes - HD RNS-E - Various other bits - 555PS/832Nm
"Taz"- C7 RS6 - MRC stage 2 745PS/1095Nm
12' Cayenne Turbo, B7 RS4, S3, Cupra R, XJR, EVO VII, STI8,5,2&WRX, 106 GTI&XSI, other crap.
Re: Problems after removing cats
Problem with coding them out without physically deleting is you don't get any warning when the system develops a vacuum leak. Not until you start getting trim problems, and even then, it won't throw a code that's directly related.
Daytona RS6 C5 Avant. Viper'd, Billies, Waggers, MTM box brain, C6 stoppers, xcarlink, R8 coolant cap (woohoo)
///M3 E46 | XC90 (V8, natch) | Passat GTE | RR Classic V8 flapper
"The major difference between a thing that might go wrong and a thing that cannot possibly go wrong is that when a thing that cannot possibly go wrong goes wrong it usually turns out to be impossible to get at and repair."
///M3 E46 | XC90 (V8, natch) | Passat GTE | RR Classic V8 flapper
"The major difference between a thing that might go wrong and a thing that cannot possibly go wrong is that when a thing that cannot possibly go wrong goes wrong it usually turns out to be impossible to get at and repair."
Re: Problems after removing cats
+ 1Daveperc wrote:1) FON
2) Removes Cats, and car goes to the dogs!
3) Get it into MRC or Unit 20 to unscramble the mess your "Expert" has got you into.
4) With proper report on what's been done demand money back from "Expert" - nb: "ex= has been; "spert"= drip under pressure
5) Enjoy your new car
6) Rule 1, or it's a myth!
Dave
No matter where you go, there you are.
Re: Problems after removing cats
Thanks for the useful info. I know it's a bit of a mess. I'll get it sorted.
Viper'd, QTP exhaust valves, Wagner'd, dogged(no cats!)