PO133 oxygen sensor & PO722 emissions codes

Marvin

• 85242 Answers
• Posted on Dec 11, 2008

SOURCE: Service Engine soon light Code P0133

In most cases this means the O2 sensor is defective.

SOURCE: emissions test comes up not ready - can't pass inspection

Under the hood, there is a fuse block. I believe it is on the driver's side of your vehicle. Open that box, and pull the "ECU" fuse. Leave the fuse out for at least 5 minutes. Put the fuse back in, start the car, and let it idle for at least another 5 minutes. Do not drive the car, touch the gas, or even look at the gas pedal for these 5 minutes, as the ECU is remapping itself. This will properly reset the ecu and clear the codes. After this you may drive the car.

PAUL MC G

• 1280 Answers
• Posted on Oct 18, 2009

SOURCE: Having the same problem the other guy described.

First of all, these codes are what are called "Powertrain Trouble Codes' (that's what the "P" means P=Powertrain). TCM Request (Transmission Control Module = TCM). The request was to turn on the 'Check Engine" light.
P0720 - output speed sensor circuit malfunction
P0715 - Input speed sensor (turbin speed) circuit malfunction
P0442 - Evaporative Emission System Leak (Small Leak)
P0455 - Evaporative Emission System Leak (Large Leak)
Check fuel filler cap problems - for Evap Emiss leaks
Replace the pulse generators & have the trans fluid replaced/flushed.
The Main Catalyst System Efficiency Bank 1 Is P0420, not P0442
If you had P0420 code, the catalytic converter is shot... and that's an expensive component.

SOURCE: 2003 Hyundai Elantra GLS. Check engine light, code PO133

Did you use a aftermarket O2 sensor or a genuine Hyundai one? If it's an aftermarket one it may be bad or not as good as the OEM one. See here for more details and other potential causes: P0133

SOURCE: trouble code shows po452 which is the evap

P0452 Evap.Emission System-Pressure Sensor Low Input

The evaporative emission control system prevents hydrocarbon vapors from escaping from the fuel tank into the atmosphere where they could form photochemical smog. Gasoline vapors are collected in the charcoal canister. The Fuel Tank Pressure Sensor (FTPS) is an integral part of the evaporative monitoring system. The PCM monitors the FTPS signal to detect vacuum decay and excess vacuum. The FTPS measures the difference between the air pressure inside the fuel tank and outside air pressure to check the purge control solenoid valve operation and for leak detection in the evaporative emission control system by monitoring pressure and vacuum levels in the fuel tank during the purge control solenoid valve operating cycles.