Well, my NSX arrived on Wed, and within the first ten miles, it threw P0420 (Catalytic Inefficiency Bank 1 code). The car has some mods, including Comptech exhaust, which is the possible culprit. Upon pulling the codes, I was a little relieved to see it was just a P0420, as I'm used to seeing that code on my WRX's, which tend to throw a P0420 when you remove two or more of the three cats that they come with.
Anyway, the previous owner asserts that this code never came up in the 1000 miles he ran that exhaust, although he said Comptech had cautioned him that the car might throw a CEL due to the exhaust.
Last night, about 150 miles since last clearing the code, it popped up again, joined by P0430, which is basically the same code, but for Bank 2. I once again checked and cleared the codes, but now I'm a little concerned about passing state inspection, as the car will fail if there are any codes present, or if its not in readiness status due to recently cleared codes (what puts an NSX into readiness, anyway?). Also, is this a common problem with Comptech's exhaust? I guess my only way to figure out if the catback is really causing the problem is to swap the stock exhaust back on and see if it throws the code again. I suppose its always possible that the cats are failing, or that the rear o2 sensors need to be replaced, although I doubt it.
Also, I tried a search on P0420, but it yielded very little useful info.
Thanks!
Anyway, the previous owner asserts that this code never came up in the 1000 miles he ran that exhaust, although he said Comptech had cautioned him that the car might throw a CEL due to the exhaust.
Last night, about 150 miles since last clearing the code, it popped up again, joined by P0430, which is basically the same code, but for Bank 2. I once again checked and cleared the codes, but now I'm a little concerned about passing state inspection, as the car will fail if there are any codes present, or if its not in readiness status due to recently cleared codes (what puts an NSX into readiness, anyway?). Also, is this a common problem with Comptech's exhaust? I guess my only way to figure out if the catback is really causing the problem is to swap the stock exhaust back on and see if it throws the code again. I suppose its always possible that the cats are failing, or that the rear o2 sensors need to be replaced, although I doubt it.
Also, I tried a search on P0420, but it yielded very little useful info.
Thanks!
I was driving in the rain, and decelerating from ~25 mph for a light, as I slipped it from 2nd to neutral, the car just died. It started right back up, but then at the very next light, the same thing happened, and the car could not hold an idle, forcing me to manually hold the throttle open at around 1k rpm, as I was paranoid to let it stall again, fearing the car might decide not to start back up at all, leaving me stranded in heavy rain. Upon one of the start ups, the car hunted for idle, reving repeatedly between 500-1500 rpm, like a Civic w/a fast idle valve problem. This is very disconcerting to me, to say the least. Now I'm stuck with an NSX with issues. Thank God for this forum though, you guys are tremendously helpful and resourceful.
I also took solace in how amazingly well maintained the exterior of the car is, and assumed the previous owner was equally meticulous in maintaining the rest of the car.
