Balto82

Went to autozone and they scanned it got the PO420 code bank 1. I know other people have thrown codes on zzp downpipe. If I put in a new sensor should the code go away? I also been reading about the defouler but isn't that for the rear o2? Also today when driving a light came on that was never there. First was check engine light, now I have a light on. It looks like a car with a lock on it? What does that mean?

TommyP

iTrader: (2)

the p0420 is for the rear 02 sensor, it's because of your aftermarket downpipe.There's nothing wrong with the sensor, replacing it won't do anything. A defouler might work, or it might not. The code you had read is for bank 1, sensor 2, which is the rear 02. Just ignore it, or get a tune and have it turned off. The car with a lock on it light is the security light, no idea why that would be on.

BLKLS

Get the defouler, clear the code. It's for what you have a cat code. Sounds like a security light.

Balto82

I hope the defouler works. Because if I delete the rear codes I will not pass emissions right?

TommyP

iTrader: (2)

if all they do is hook up a ecu scanner then you'll still pass. If they actually use a test meter to check the exhaust you're screwed either way.

LS6Rally

iTrader: (14)

^ in MA they hook up to your OBDII. if the is a cat efficiency code, it will NOT pass.

i am having this issue now, and its rather frustrating. i know its my own fault, i chose to put the DP on there. i installed a defouler over two months ago, and the cat monitor hasnt gone "ready" yet.

Balto82

Well got the defouler gonna put it on. Ifi can get the code to go away I'm screwed with emissions they hook up to ob2 here looked under the hood, they check all monitors. The only thing they didn't check is exhaust not that I have one yet. Hope this work. What's a down pipe that won't through codes on a 2.2?

K-Train04RL

iTrader: (1)

they all eventually will. a high flow cat is a less effiecient cat, and the p0420 is a cat low effieciency code.

TommyP

iTrader: (2)

Stock. If all they do is run a obdII test, then as long as you can get the code to go away you're fine.

nhanson

iTrader: (1)

Doesnt affect anything. I even took out my rear O2 and put my wideband there

Balto82

I thinkk states that are odopting cali emission is a lot more strict. It says on the emisions booth that you can't just clear codes. And al monitors must be set so I don't know atleast I got a year to figure it out!

TommyP

iTrader: (2)

You could always just do what everyone else does, swap the stock one back in, then take it back out after the test is done. Only need to do it once a year.

Balto82

Yeah but I'm going to be peacing together a turbo. This dp will bolt to the garret elbow and I'm going to get a custom turbo manifold built. So what happens if I have a turbo setup than put stock downpipe back on it??

climb385

when u get the car tuned have them turn off the rear o2 sensor and u wont have to worry about a damn thing, it will pass with flying colors

Balto82

Well I got a code scanner and defouler. Drilled them out put it on. So far its working. Havnt got a code. The only monitor that's not set is EV? That doesn't have anything to do with a downpipe right?

cobalt_sport08

iTrader: (1)

thread revive.. I've got this problem now too. Will the engine run any differently with the CEL on??

TommyP

iTrader: (2)

not even a little

Cobalt08LS

iTrader: (15)

geta defouler off ModernPerformance and reset the battery.
did the trick for me!

nhanson

iTrader: (1)

I just removed my O2 sensor and had codes deleted.

cobalt_sport08

iTrader: (1)

I keep removing it with my torque app but they come back about every 3 days

Balto82

Either get a vibrant defouler or delete the code those are your only option.