I have some Velocity 200 cell cats on a 4.3 v8 which are giving me a CEL. I have put a few hundred miles on them and am due for inspection, but still have the CEL on. I am in NY which allows for one sensor to be "not ready". I'm aware of some ECU tunes that shut down the sensor, and I assume shutting down two O2 sensors will put me over that limit.

I'm curious how anyone else has passed inspection with these cats? I am also curious to what degree O2 sensors may be failing? A dealer has assured me the sensors do not need to be replaced, but not sure how they can determine that. I am wondering if it's worth just trying fresh sensors for the hell of it.

 

Can you post the code, codes that you are getting? If they are in fact oxygen sensor codes and not efficiency monitor codes (P0420) you most likely need to replace sensors. Codes P0130, P0150 should indicate sensors not responding or slow to respond. Lots of info already posted about changing oxygen sensors, do a seach.

 

I will do a rescan of the codes later today to confirm, but these were not the 130/150 codes. I know the sensors themselves did not throw codes, but just wondering if the reading could be very slightly off. I know the check engine light had come off a couple times, so the amount of o2 is not far over the limit, but just wondering if fresh sensors may give a slightly better reading and pass.

From reading many posts here it sounds like many people here have the VAP high flow cats and do not have any issues with a CEL, so wondering what may be different for me in this case.

Thank you

 

I also had the CEL come on after I installed the VAP 200 cell catalysts on my 2008 Vantage Roadster, I emailed Stuart and Chris and they sent me a revised ECU map that defeated the CEL.

 

Thanks, I just ordered that, so fingers crossed. Were you able to pass emissions with that?

 

It was a couple of years ago but from what I remember, you shouldn't have problems passing emissions with the 200 cell cats. The software tweak Chris made was just to defeat the check engine light.

 

Sorry. To answer your question, yes, it did pass emissions in Virginia.

 

Simple solution, replace original cats.

 

it is possibly the O2 that needs replacing