[TheLumina]

Trying to trade in my car with minimal effort. I have a CT Turbo high flow catted downpipe for my stage 2 tune but want to flash back to stock. Was wondering if I could leave the catted downpipe in there on stock tune or would it throw a check engine light?

[Hiflyer731]

Likely will throw a CEL. Most tunes designed for high flow or catless downpipes will block the CEL. Might not happen immediately but probably fairly soon.

[G.Newt]

Depends on the quality of the cat. MY CG didn't when I was stock. I know the AA won't as well.

[e30 4 life!]

Originally Posted by G.Newt

Depends on the quality of the cat. MY CG didn't when I was stock. I know the AA won't as well.

^^^this

[WrxToBeamerGuy]

AA does not even on a 600whp car with tons of mods.

[SimonBMW1]

I found it requires highway/motorway driving for 20 miles or so before a light appears. Download the MHD app, on a free license you can clear code. Light disappears, you can trade car in etc. Also ISTA can clear it.
Once mapped i never got the light.

Also some people use this
https://mtcmotorsport.co.uk/products...iABEgI6QPD_BwE

[SpoolinAddict]

Originally Posted by SimonBMW1

I found it requires highway/motorway driving for 20 miles or so before a light appears. Download the MHD app, on a free license you can clear code. Light disappears, you can trade car in etc. Also ISTA can clear it.
Once mapped i never got the light.

Also some people use this
https://mtcmotorsport.co.uk/products...iABEgI6QPD_BwE

Is there one available for N55 EWG? is there US shipping

[mike@x-ph.com]

Originally Posted by WrxToBeamerGuy

AA does not even on a 600whp car with tons of mods.

+1 the active autowerke downpipe uses EPA-approved GESI cats rated at 850 whp.

It also comes with a no CEL guarantee.

[TheLumina]

Originally Posted by SimonBMW1

I found it requires highway/motorway driving for 20 miles or so before a light appears. Download the MHD app, on a free license you can clear code. Light disappears, you can trade car in etc. Also ISTA can clear it.
Once mapped i never got the light.

Also some people use this
https://mtcmotorsport.co.uk/products...iABEgI6QPD_BwE

Thanks for the info on MHD, gonna give it a shot. Any idea if the CEL come back even after clearing with MHD?

[SimonBMW1]

Originally Posted by TheLumina

Thanks for the info on MHD, gonna give it a shot. Any idea if the CEL come back even after clearing with MHD?

Yes light will come back on after a few miles of either driving on motorway/highway. think 100 miles or so.

[TheLumina]

Originally Posted by SimonBMW1

Yes light will come back on after a few miles of either driving on motorway/highway. think 100 miles or so.

Ah okay, I thought clearing codes through MHD would mean it covers it completely. It’s the same as clearing codes using a regular OBD reader then?

[sigterm2.0]

Originally Posted by TheLumina

Ah okay, I thought clearing codes through MHD would mean it covers it completely. It’s the same as clearing codes using a regular OBD reader then?

Yes.. MHDs code clearing is just a regular code clear, it is not a "code suppressor".

And it's a free option. You don't need to purchase a license to read /clear codes in MHD. I prefer the MHD code reader because it has a handy feature that lets you email the report.

[andyb313]

you could use MHD to flash it back to MHD stage 0 map and then disable the cel? car would perform as stock and wouldnt throw the CEL

[TheLumina]

Originally Posted by andyb313

you could use MHD to flash it back to MHD stage 0 map and then disable the cel? car would perform as stock and wouldnt throw the CEL

I've done this and CEL comes back after a drive or two, seems fast when you go on the highway. I might just flash in the parking lot before trading it.... they know it's a straight pipe already.

[BaconDouble]

Originally Posted by mike@x-ph.com

+1 the active autowerke downpipe uses EPA-approved GESI cats rated at 850 whp.

It also comes with a no CEL guarantee.

Agree 100% and got mine from X-PH about 2 years ago.
2 years now of passing state emissions no problem at all.

You do need to flash back to stock if tuned, and have all of the readiness monitors "set" by doing a "BMW drive cycle" or two.

I don't understand people not spending the extra $600-800 or so for an AA catted downpipe over some other high-flow brand without a "NO CEL guarantee" and then having to deal with all of the emissions issues (and your time and money) it causes - especially if you have to change back to the stock DP for emissions and then switch it again afterwards.

I my state I have to deal with safety and emissions every year so it's a big deal.

[mike@x-ph.com]

Originally Posted by BaconDouble

Agree 100% and got mine from X-PH about 2 years ago.
2 years now of passing state emissions no problem at all.