Check Engine Light
 

Hey all,

So this past weekend I did an entire exhaust over hall with brand new 2.5" pipes to an x-pipe to a muffler delete. They're bigger than the 2.25" pipes that come factory. I had the NPP exhaust a while back but did a muffler delete on that a long time ago.
I unplugged the sensors for the NPP exhaust for the first time ever (because they're non existent now) and it caused the CEL. Anyone know of a tune or anything to get rid of that light?

do you have the code ? what code is it throwing?

The code is showing the emissions system. That's the fuel management system is not functioning correctly. But I've never gotten a CEL until I unplugged those sensors. The car runs fine, starts up just fine too.

As he said, what is the exact code? Should start with a "P" followed by 4 digits

I'll have to go today and get the actual code. I don't have a device that checks it. I'll tune in when I get the code number

Thanks

once you have the code you can see what's wrong..

do you have A8 or M6?

I have the A8. I'm thinking its those sensors, or they didn't weld correctly and theres a leak somewhere. I'll get the code checked out today after work though and see whats up. They cleared the code yesterday at the exhaust shop but it came back after i turned the car off and then back on. I just didn't ask them what the code was.

yeah the A8 are tricky because of the AFM sensors ..

check for leaks also .. i heard when you have a leak it will cause a CEL( but normally around the cat only ) ..

The factory diameter exhaust is actually 2.75" not 2.25"

On the SS it is, not the V6

You can't just unplug the AFM sensors. That is why you have a check engine light. Why would you think it was OK to just unplug them?

He mentioned NPP sensors but wondering if he actually unplugged the AFM connections like you mentioned. Yea definitely can't do that without a CEL.

Are there NPP "sensors"? And, if so, what do they do? Can't see how it matters if the NPP valves are open, closed, working, or not, other than to change the noise.

Might have meant the actual connections for the NPP valves. Think the AFM valves work the same way though.