About two weeks ago I installed the DC header and the Megan Racing downpipe w/ CEL eliminator,(O2 sim.), in addition to the AEM cai and Skunk2 cat-back that I've been running since day one. Up until yesterday everything had been great, loud as f**k!!! but great, no CEL under a variety of driving conditions. Yesterday I was going for a 2 hour highway drive so I decided to put in the muffler silencer and after about an hour on the highway the CEL light came on. When I got to my destonation I removed the silencer and disconnected the battery. I drove the return leg of the trip and about 50 miles additional of city driving since and no CEL. Why does use of the silencer trigger the CEL? Thank you for any insight.

 

I am using the "Ichiba O2 simulator adapter, CEL mechanical fix". Your reasoning is pretty much what I thought might be the case, seeing as how all my piping after the header is 60mm(+-) but the silencer then reduces the size back down to 1.75" so the noxious gases then have time to swirl around and accumulate?

 

Thank you, sounds like a possible solution... but brings another question; Can you move the sensor too far away from the exhaust stream and trigger the CEL for the opposite reason,( not reading enough gases)???

 

From what I found out is that the sensor needs to be a good amount away from the exhaust flow. When I did my own CEL fix (o2 Defouler) my CEL would pop back on after normal driving.

I then bought a T1R testpipe. Their o2 sim was extented out pretty far. Id say a good 3-4in from the bung and the hole is small. Basically no air seems to get to the o2.

Hows the power gain with those mods? Get some sound clips please.

 

Thanks for the input guys. The power and the fun-to-drive factor of this car is up more than noticably. I love this car. I don't know how to add sound clips but in its current state without the silencer this car is ferociously loud. I mean like race car, rattle interior parts, turn the stereo up past 30, can't have a normal conversation loud. But amazingly just cruising along with slight pressure on the gas on level ground,( very light load), this car is almost as quiet as stock, kind of like a sweet spot where it resonates just right. It looses this effect with the silencer but gains a nice even, deep tone that is not over powering and what seems like a smoother powerband. When I added the DC and Megan products the power band changed noticably from just running the AEM and Skunk2, definately some loss below 2k, a little burp of power around 2700 to 3k, and then pulling strong from 3500 on up, stronger as you climb and reaching red-line with great ease. Sorry no sound clips or dynos but I hope this gives you some idea. Thanks again.