Wideband / Boost/Fuel/Oil Pressure

by Michael Decipha Ponthieux

Posted: 2016-11-17

Last Updated: 2018-02-07

NOTE: It IS NOT RECOMMENDED to remove or disable the EGR unless absolutely neccessary.

If you do not have the ability to add in an additional bung for the wideband you have the option to disable hego2 (driver side) and install the wideband in that bung while tuning. See the Tuning Tips Write Up for more details.

NOTE: A wideband is too slow and not accurate enough to simulate a narrowband, I highly advise to

The full ecu pin out is available by CLICKING HERE.

You should always source a fused 12v ignition feed directly from the fuse box. Be sure you tap into the FUSED out and not the UNFUSED in.

Now, look up the wideband transfer function for your wideband, it should be in the booklet that came with it. You will need to know the transfer to verify it with the table below.

WBo2 - AEM | |

Volts | Lambda |

5.12 | 1.230 |

4.50 | 1.230 |

3.00 | 0.990 |

0.50 | 0.580 |

0.00 | 0.580 |

(2.375 * (X/12800) + 7.3125) / 14.7 |

WBo2 - LC-1 | |

Volts | Lambda |

5.12 | 1.523 |

5.00 | 1.523 |

2.50 | 1.020 |

0.00 | 0.500 |

0.00 | 0.500 |

(0.2046 * (X/12800) ) + 0.5 |

WBo2 - PLX | |

Volts | Lambda |

5.12 | 1.360 |

5.00 | 1.360 |

2.50 | 1.020 |

0.00 | 0.680 |

0.00 | 0.680 |

( 0.136 * ( X / 12800) ) + 0.68 |

WBo2 - B | |

Volts | Lambda |

5.12 | 1.540 |

5.00 | 1.540 |

2.50 | 1.010 |

0.00 | 0.500 |

0.00 | 0.500 |

(7.35 + ( X / 4267 )) / 14.64 |

WBo2 - C | |

Volts | Lambda |

5.12 | 1.379 |

5.00 | 1.379 |

2.50 | 1.023 |

0.00 | 0.683 |

0.00 | 0.683 |

X * 0.000010625 + 0.683 |

WBo2 - D | |

Volts | Lambda |

5.12 | 1.xxx |

5.00 | 1.xxx |

1.50 | 1.000 |

0.00 | 0.xxx |

0.00 | 0.xxx |

(9 + ( (X/12800) * 1.4)) / 14.7 |

WBo2 - ZT-3 | |

Volts | Lambda |

5.00 | 1.333 |

1.50 | 1.000 |

0.00 | 0.653 |

0.136 * (X/12800) 0.653 or (2 * (X / 12800) + 9.6 ) / 14.7 |

If your transfer is not listed, post your transfer function in the Wideband Thread to be added in.

In all cases, after you have selected your wideband you must

then click on conversion

at the top you'll see the equation click on set

X is the EVP raw input voltage which is the widebands actual output voltage, 0 - 65535 a/d counts correlating to 0v to 5v respectively.

A wideband outputs a linear voltage based on air fuel ratio, thus one can logically infer the equation for the wideband transfer is a simple interpolation equation. The following is the basics to compute the equation.

- Max Lambda Measureable - Min Lambda Measureable = Z
- Z / 5 = Y ;{Max Voltage Output - Min Voltage Output (5v - 0v)}
- ( {Y} * (X / 12800) ) + Min Lambda Measureable ; Note: x/12800 is to convert ad counts to voltage

For Reference:

32,000 ad counts / 12800 (ad to volt conversion) == 2.5 volts

so for an equation that is 7.35 + ( X / 4267); 3.1v [stoich which correlates to ~16.6 AFR for a 2.5v stoich] the correct equation is 0.16222 * ( X / 12800 ) + 0.5

in tunerpro edit the ADX >> Values >> WBo2

then click on conversion

at the top you'll see the equation click on set

at the very tail end of the equation add

* x.xx

x.xx being the percentage your wideband is reading off (from 0.90 to 1.10)

If your wideband is reporting more than 10% off then you have the wrong transfer selected.

In all cases, if you are getting a REMOTE TUNE be sure to notify the tuner.

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