Has anyone been able to drive around with an aftermarket DP without any CEL issues after a couple of hundred miles? If so please state whether you have a cat, size, and brand please. Considering getting one but I read about lots of people with CEL issues. Thanks

I drove for thousands of miles with my Alta turbo back before a cel came on, which was around the time I started using the unichip. I put the spacer on the 2nd O2 sensor but that did nothing, and I've had the cel on ever since...I don't see why we can't just disable that code when a real ecu tune comes out.

I have a milltek back section on my car (resonator and back box) and its connected to a Ragazzon catless downpipe. I have done over 1000 miles since getting the downpipe fitted and have no CEL.Its inner diamter is 2.5". It costs about 200 Euros so its an absolute bargain! You can see more info about the Ragazzon competition downpipe here : https://www.northamericanmotoring.co...d.php?t=157589

I have a ggr downpipe 2.5" 100 cel cat and it bolts on to the stock exhaust or the Invidia. I have the cel on even with the 02 extender installed.

But I really dont care about the cel the sound and performane is great.

I have a Milltek full system on for over 6,000 miles and no lights at all..sounds great, high quality and craftsmanship and you can get it direct from Lohen in the UK worth the call, I got my DP in 4 days from UK the catback was shipped from stramosphere, but I do not think they carry the MINI line no more.

Full ALTA 3in Turbo back, CAI, No CEL EVER 45000 kilometers, Numerous European track sessions...like every weekend. American Spec.

The safe workaround is to buy an exhaust like the Miltek Turbo exhaust that improves flow more than a cat-back system by removing the second catalyst but doesn't mess with the o2 sensor monitored section of the exhaust. You could also have a local shop do an equivalent custom setup for about half the price.

I don't quite understand how those with catless downpipes aren't getting CEL's, when so many with legal aftermarket cats get them. Anybody know why?

Through an ECU reflash it is most definitely possible to disable CEL's caused by this specific issue. Evotech said they can do it.

I keep getting a code for the 2nd o2 sensor I am going to try the spark plug spacer like scott48 but it dosent look like it worked for him. Is anyone else gettin anyother codes than just bank slot 2 ot whatever it is? This **** is annoying!!!!!!!!!! DAMN YOU ALTA

I have a secondary O2 extender in place so that the sensor is further away from the exhaust stream.... however. I get a CEL but its not due to emissions.. its due to the secondary sensor taking too long to warm up!!
So it looks like you cant really win lol

Well now this is just retarded. I wish I would have known this **** cuz I woulda ran a straight pipe if I have a check engine light no matter what. GRRR

KEEP ME IN THE LOOP DAMN IT!

Seriously, get me an ALTA2 in the loop when you have an issue or concern with our product or anyone's! We LIKE to help out. We can provide the extender for you as well as double check some other things free of charge. As witnessed here, there is some with a persistant issue and others with ZERO. On ALL of my R56's I have owned. (On my 6th right now! Yikes) I haven't had the issue. But other clients have. Please PM me and ALTA2 so we can help further. Sorry for any inconvenience!