Which o2?

[highPSI-S4]

I have this code P0431 or 16815

Warm up Catalyst; Bank 2; Efficiencyelow threshold
P0431- 35-10- - - Intermittent

It just says the bank and not the sensor. I know that Bank 2 is the driver's side but which sensor is it?

this is the only code i'm throwing so far aside from misfires at WOT.
I'm sure i can check the o2 voltages but don't know what there suppose to be.

[old guy]

I have this code P0431 or 16815

Warm up Catalyst; Bank 2; Efficiencyelow threshold
P0431- 35-10- - - Intermittent

It just says the bank and not the sensor. I know that Bank 2 is the driver's side but which sensor is it?

this is the only code i'm throwing so far aside from misfires at WOT.
I'm sure i can check the o2 voltages but don't know what there suppose to be.

It is the rear sensor that determines the cat efficiency. It is very likely that the problem is the cat and not the sensor. Here is an article that will help with checking the sensor. Clicky click It's for a different motor but the same principles apply.

[highPSI-S4]

It is the rear sensor that determines the cat efficiency. It is very likely that the problem is the cat and not the sensor. Here is an article that will help with checking the sensor. Clicky click It's for a different motor but the same principles apply.

Thanks, that was helpfull. Only thing is the rear o2's are somewhat new and the cats are very new, like 8,000 miles ago new. Maybe i got the wrong kind of cat? I was also under the impression that the rear o2's don't affect driveablitiy or least not as much as the front o2's. What kinda cats should i buy?

[old guy]

Thanks, that was helpfull. Only thing is the rear o2's are somewhat new and the cats are very new, like 8,000 miles ago new. Maybe i got the wrong kind of cat? I was also under the impression that the rear o2's don't affect driveablitiy or least not as much as the front o2's. What kinda cats should i buy?

The rear sensors do not affect the driveability of the car. They only "tattle" on the cat. The cat should be covered for 8 years or 80K miles. I would check with the installer before spending any more of your own $$ on a new cat.

Good luck!

[highPSI-S4]

Well i'm assuming your talking about the warranty on stock cats, i'm stg2+ with down pipes and custom catback. And i had high flow cats put in to replace the test pipes i had.

[old guy]

Well i'm assuming your talking about the warranty on stock cats, i'm stg2+ with down pipes and custom catback. And i had high flow cats put in to replace the test pipes i had.

In that case I would just reset the code and see how long it takes to come back. It shouldn't have any effect on performance. You could also try one of these on your cat to see if it helps: Clicky click

[highPSI-S4]

In that case I would just reset the code and see how long it takes to come back. It shouldn't have any effect on performance. You could also try one of these on your cat to see if it helps: Clicky click

This is the second time it came back, just VAG'd it today after clearing it a week ago.
Yeah funny thing is i had those when i ran my test pipes, but when my friend who owns his own shop insatlled put in my cats he didn't give me the de-foulers back, i just found out last week he's using them on his 04 SVT cobra.

I'll try something. Thanks for the help

[AAAA]

yyyyeah, if you don't have it in your software, you need to get the spacers back. high flows will throw that code too

[highPSI-S4]

yyyyeah, if you don't have it in your software, you need to get the spacers back. high flows will throw that code too

I didn't know that. Guess i'll be buying another pair.

more money to spend