NOTE: DO NOT take measurements while radiator cooling fan is operating.

NOTE: If the adapter has been used for fuel system testing, DO NOT use it for emission sampling. Residual fuel traces will make CO/HC readings inaccurate.

Connect (VAG 1363) CO tester to CO tap tube, near Heated Oxygen Sensor (H02S), using adapter (VAG 1363/3). See Fig 1.
Start engine and let idle. CO content must be 0.5-0.9 percent. See IDLE SPEED & CO LEVEL table.

NOTE: Failure of one spark plug increases CO content significantly.

If NO: Ensure that all spark plugs are operating properly.
If spark plugs are Okay, but CO is still NOT to specification, perform the following steps:
- Read DTC memory again.
- Initiate Output Diagnostic Test Mode (DTM). See OUTPUT DIAGNOSTIC TEST MODE in SELF-DIAGNOSTICS .
- Check engine Basic Setting values in display channel 3 (display field, oxygen sensor).
Make the necessary repairs.

Fig 1: Connecting Carbon monoxide Tester To CO. Tap Tube (Port)

Courtesy of AUDI OF AMERICA, INC.

IDLE SPEED & CO LEVEL

Application

Idle RPM

CO Level

2.22L Turbo

Man. Trans.

⁽¹⁾ 770-830

0.5-0.9%

⁽¹⁾	Trans. in Neutral. Radiator cooling fan clutch not engage.

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.

• Brakes feel soft, pull hard to one side, or make grinding noises.

• The engine overheats, stalls repeatedly, or misfires under load.

• You are missing required tools, torque specs, or safe lifting equipment.

• You are not confident in the next step or safety outcome.

Safety Warning

Carbon Monoxide Content: Testing

Use the Manual With the Right Hardware

When to See a Mechanic