Emissions Readiness

I've almost given up, I am trying to get my car to pass NYS inspection and to no avail it won't pass. could an exhaust leak cause readiness failure i.e vband clamp gasket ?


CCTA mk6 GTi btw.

Codes? Also if you are ever under your car and near the rear O2 sensor, can you send a picture of the car side connector and the color of the wires and where they go

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May be a dumb question but are you changing the ECU back to the stock map or are you leaving the APR tune on?

The APR map disables the readiness monitor for the secondary O2 sensor.

jhstl said:

May be a dumb question but are you changing the ECU back to the stock map or are you leaving the APR tune on?

The APR map disables the readiness monitor for the secondary O2 sensor.

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Im stuck on Stage 2 dont really have the option of going back to stock

jhstl said:

May be a dumb question but are you changing the ECU back to the stock map or are you leaving the APR tune on?

The APR map disables the readiness monitor for the secondary O2 sensor.

Click to expand...

Not a dumb question at all, i did not even think of that.

flight1us said:

Not a dumb question at all, i did not even think of that.

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That would be my guess as to why it won't set readiness. Can you force it with vagcom?

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any links on how to set readiness?

flight1us said:

any links on how to set readiness?

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I could be wrong but I don't think you can change this on the APR stage 2 file.

I bought my GTI with an APR tune on it and couldn't pass emissions either and I had to take it to the APR dealer, flash back to stock and install an O2 sensor spacer. They drove it around for 25 miles, passed emissions, and re-flashed it back to stage 2. It ran me a few hundred dollars. I ended up having them add ECMS map switching and loading the stock map onto one of the slots so I could switch back if I ever needed to.

If there is a way to enable the secondary O2 sensor readiness via vagcom or ODBeleven i would be very interested in how.

You’re not going to pass NYS inspection with APR Stage 2 software active. There will be too many monitors disabled/not ready.

A stock non-test pipe map has to be loaded for all to read properly via OBD2. Then you’ll have to deal with spacers, etc. to suppress the CEL

2012TP said:

You’re not going to pass NYS inspection with APR Stage 2 software active. There will be too many monitors disabled/not ready.

A stock non-test pipe map has to be loaded for all to read properly via OBD2. Then you’ll have to deal with spacers, etc. to suppress the CEL

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Why would i have to use spacers if the test pipe file is being loaded?

flight1us said:

Why would i have to use spacers if the test pipe file is being loaded?

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I'm not sure how to explain it accurately from a fluid dynamics perspective, but using a spacer introduces some turbulence for the O2 sensor and if I understand correctly, the turbulence is basically tricking it into reading that everything is all right.

flight1us said:

Why would i have to use spacers if the test pipe file is being loaded?

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Two options. Swap back to stock downpipe or...


You need the rear O2 sensor to be enabled. The rear O2 sensor monitors catalyst efficiency. All aftermarket downpipes have a free flowing catalytic converter or non at all. This inevitably makes the air flowing by the rear O2 sensor less clean. When more pollutants are detected by the rear O2 sensor it triggers a trouble code and illuminates the check engine light. Tuners disable the rear O2 sensor on all tunes meant for aftermarket downpipes to prevent the check engine light. While there is no check engine light the, rear O2 sensor is a state of NON-readiness. Depending on the state, you are only allowed to have a certain amount of readiness monitors in a non ready state. So, in order to get around this you need to flash to a tune that enables the rear O2 sensor. This is usually stage 1 or stock. If this option is t available to you, you need to contact your tuner, or go to the dealer and have them flash you back to stock. Once you have been flashed to stock you then need to use an O2 spacer for the rear O2 sensor. This effective pulls the tip of the sensor out of the downpipe further away from the exhaust stream. This fools the sensor into thinking it’s within ecu’s efficiency parameters. So, now your car has no check engine light and rear O2 readiness monitor is ready while still running the aftermarket downpipe.

Get a tuner that forces all readiness monitors to pass.

Just an FYI. Readiness cannot be "forced". I believe APR disables the last 02 sensor with stage 2 tune to keep CEL from showing up. That disabled 02 sensor will show up as bad during readiness and there is no changing that, you will need a different tune.

As mentioned you will need a tune that does not disable the 02 sensor, stock tune is an option or switching to most other brands of tunes will do as well.

With no cat or a hi-flow cat in place you will fail. The test is looking for a significant difference between first 02 and second 02 to confirm the catalytic converter is working and it has cleaned up the unburnt fuel. You can fool the system by pulling the last 02 out of the main air stream by using a spacer. This allows a lot less of the exhausting air to pass around the sensor making the system think the exhaust has been cleaned up.

The fool proof option is to put OEM downpipe and 02 sensors on and run a stock tune.

Thanks for all this helpful info