2.0L RV6 Catless vs Catted Downpipe

mvela

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Curious as to how it will sound with the DBX!
I’m kinda hoping it doesn’t change the sound much. I really like the way my exhaust sounds now
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long_meats

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Well I just ordered my downpipe black ceramic coated. Tired of thinking about it lol. I just pulled the trigger
Just an update regarding the CEL- Last night I unplugged both terminals of my battery for an hour to reset the ECU and the CEL went off, but came back on today :/

Looks like KTuner it is
 

a c i d.f l y

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CEL comes on, stays for two days, goes away the next morning, fine for a couple days, then comes back on for two days. Rinse, repeat, about four times now.

It is definitely louder than stock, but no where near as tinny or raspy as catless. It's gutteral and clean. Sounds fucking amazing, honestly, and accentuates intake perfectly.

Second O2 sensor defouler needs some tweaking. Seems to come on mostly after cold start and low operating engine speeds. Well, actually might be a bit random. Just seems consistent in it coming on every couple days, then going away. Catless flagged up almost immediately. Anyone running it without a tune? Though not sure why you'd bother without a tune.
 

mvela

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Just an update regarding the CEL- Last night I unplugged both terminals of my battery for an hour to reset the ECU and the CEL went off, but came back on today :/

Looks like KTuner it is
Well you will like the extra power from the ktuner, I know I do. Definitely worth it
 

long_meats

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Well you will like the extra power from the ktuner, I know I do. Definitely worth it
Ah yes I already have KTuner, I was referring to using it to make the CEL light go away, but before I do that I'm hoping to see if it goes away by itself first like it does for acid.fly as I will need to get a state inspection soon-ish and have read that disabling the CEL light with KTuner can cause you to fail.
 


mvela

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Ah yes I already have KTuner, I was referring to using it to make the CEL light go away, but before I do that I'm hoping to see if it goes away by itself first like it does for acid.fly as I will need to get a state inspection soon-ish and have read that disabling the CEL light with KTuner can cause you to fail.
Oh I see. Yeah that’s why I held off for the catted downpipe so it would read properly. But at least it gets rid of the smell, I guess. Good thing you already got a ktuner. I would be upset if I got the catted downpipe and was still fighting the CEL
 

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Ah yes I already have KTuner, I was referring to using it to make the CEL light go away, but before I do that I'm hoping to see if it goes away by itself first like it does for acid.fly as I will need to get a state inspection soon-ish and have read that disabling the CEL light with KTuner can cause you to fail.
Depends on your state, if they read your OBD2 it will read the O2 Sensors in a "NOT READY" state which causes you to fail, even if there's no Check Engine Light. CEL with catted pipe stays off long enough to get a read on the OBD2 for inspection, which is all I really cared about. If it continues going off and on, I'll just turn the sensors off. I'm going to start logging, so I can see what exactly happens when it flags.
 
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mvela

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Depends on your state, if they read your ODB2 it will read the O2 Sensors in a "NOT READY" state which causes you to fail, even if there's no Check Engine Light. CEL with catted pipe stays off long enough to get a read on the ODB2 for inspection, which is all I really cared about. If it continues going off and on, I'll just turn the sensors off. I'm going to start logging, so I can see what exactly happens when it flags.
Yeah I was afraid of that. I did some research and it seems like high flow cats tend to trip codes to.
 

OilChange123

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I already have a ktuner on mine, would a catted downpipe still add a worthwhile amount of power or is best to just stick with the ktune?
 


mvela

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I’m starting to wonder if I made a mistake on ordering my downpipe. I wanted to get the best power I could while maintaining efficiency. But it seems like even with a catted version it’s still causing the service engine light. This tells me that the oxygen sensors are not reading correctly which would make the engine run inefficient therefore reducing my mileage.
 

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CEL comes on, stays for two days, goes away the next morning, fine for a couple days, then comes back on for two days. Rinse, repeat, about four times now..
Just to update- since I last posted (I reset the ECU last Wednesday by disconnecting the battery and the CEL went off but came back on the next day), the light was off again Friday and stayed off Saturday too. Haven't checked yet today, but so far it seems to be consistent with acid.fly's experience (assuming it it will come back on within the next few days). Haven't had a chance to check the OBD2 codes yet.

I’m starting to wonder if I made a mistake on ordering my downpipe. I wanted to get the best power I could while maintaining efficiency. But it seems like even with a catted version it’s still causing the service engine light. This tells me that the oxygen sensors are not reading correctly which would make the engine run inefficient therefore reducing my mileage.
I've never heard anyone report the oxygen sensors causing poor mileage, so I wouldn't worry too much (or at all) about that. My mileage seems to be the same as before installing the catted down pipe if that helps at all. It appears RV6 will stand by their product and continue to offer support to their customers by tweaking the de-fouler to eliminate the CEL issue since they did the same for the catless one.
 

mvela

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Just to update- since I last posted (I reset the ECU last Wednesday by disconnecting the battery and the CEL went off but came back on the next day), the light was off again Friday and stayed off Saturday too. Haven't checked yet today, but so far it seems to be consistent with acid.fly's experience (assuming it it will come back on within the next few days). Haven't had a chance to check the OBD2 codes yet.



I've never heard anyone report the oxygen sensors causing poor mileage, so I wouldn't worry too much (or at all) about that. My mileage seems to be the same as before installing the catted down pipe if that helps at all. It appears RV6 will stand by their product and continue to offer support to their customers by tweaking the de-fouler to eliminate the CEL issue since they did the same for the catless one.
Yeah hopefully they figure out why it keeps coming on. I was just reading that on some cars the O2 sensor after the cat is only to monitor catalytic efficiency, and on others they are actually used in conjunction with the pre-cat O2 sensor to calculate air-fuel ratio. I just don’t know how our cars utilize that second sensor. But it does make me feel a little better knowing your mileage hasn’t been affected and that RV6 is still trying to resolve this issue.
 

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I'm not the person you asked, but I installed mine 6 days ago and haven't had the CEL light come on (or any other issues for that matter).

*EDIT* The CEL came on 1 day after I posted this.
Why did your CEL come on with the catted one? Isn’t that supposed to be an advantage over the catless one?
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