Wideband readings

blacksi76 · Post by **blacksi76** » Thu May 20, 2010 5:18 pm

I have the Hondata P28 prepared ECU with the OBD2B conversion built in...I am using the NGK AFX wideband and I am currently wired into the factory O2 sensor wire on my OBD2B wiring harness and I am getting incorrect readings....Pin D14(OBD1, Primary O2 ) connects to Pin C16 ( OBD2B, Primary O2)...I am running open-loop, and my readings are incorrect, Pin D14 only reads a max 3.86 volts and this explains why on the laptop , the AFR readings go no higher than 14.56 when the guage shows a leaner reading....I have tried playing with the Voltage offset Box and I couldn't get it right, then I changed the actual Voltage on the Voltage/Lambda Conversion table ( which should be 0v-5v on the Top and 9-16 AF on the bottom)to 0v to 3.54v on the top box then 9-16 AF on the bottom box, then played with the Voltage offset and got the reading very close, but the highest ( leanest ) the AFR readings read on the laptop is 15.50AFR.....From what I have read here, realistically, I should not have had to mess with the Voltages at all to get the correct readings, or at least not as much as I did....So if I switch the AFR analog input from the O2 wire to the ELD input source and clip the R136 and R138 resistors, I should get the correct AFR readings on the laptop without messing with the Voltage offests?? Does Clipping these resistors affect the functioning of the ECU??

Post by **Spunkster** » Fri May 21, 2010 9:31 am

It's something you can try. removing the resistors will not hurt anything.

blacksi76 · Post by **blacksi76** » Fri May 21, 2010 2:10 pm

OK, I did it all, switched from the factory O2 wire which only puts out up to 3.86 volts to the D10 ELD, installed the Pin on my factory harness plug , Pin A30, removed the two resistors R136 and R138, checked for Voltage with the Multimeter, and I am getting 0-5 volts reading from the analog wire coming from the NGK AFX right to the Pin I installed into slot A30 on my factory wiring harness, switched it over in the parameters menu....went into the sensors list double clicked on the ELD section, changed the voltage from 0 min to 5 max there....went into Parameters again and clicked on the Misc., made sure disable ELD was unchecked ( actually I tried it checked and un-checked and no diference ) .... I don't know what or why this is happenning....all the posts I have read, spoken to the tech support from NGK and Hondata, and noone can tell me whats going on??? I have played with the Voltage offset box every which way and can never get it to fluctuate throughout the entire 9-16AFR.....It always Hovers in one area.....What can I do?????

Martian · Post by **Martian** » Mon May 24, 2010 12:14 pm

What do you mean it doesn't fluctuate? If the fuel tune is good it should not fluctuate that much. The guage is also showing you less data than Smanager is. The gauge only displays voltages samples every few fractions of a second where hondata will display every bit of info it gets. Take these things into consideration.

blacksi76 · Post by **blacksi76** » Mon May 24, 2010 12:56 pm

I have it figured out now, thanks, I switched the input to the EGRL, I added a pin to my harness and connected my analog wire from my AFX to that and it worked perfectly...readings are bang on....still not sure why the ELD wouldn't work, but its fixed now.....thanks for the input..