On my 2000 d16y7 I had a check engine light come on saying that the car was running lean. This was after I put on a cold air intake and header. Also because of the header I haven't put on my rear O2 but frin what I have heard that won't affect the way the engine is running. What I need to know is how to correct the fuel/air mixture so the engne light goes off and I can go through emmisions?
Any help would be appreciated thanx in advance guys

 

Well your gonna need your rear O2 for emissions, as that sensor monitors the performance of the catalyst.

You might want to clear all stored memory from the PCM, because if one day you put a cold air on it, it may freak out because just yesterday it was running with a stock airbox that didn't allow as much air to flow. If you set it to factory defaults, it will re-learn everything, based on your setup as it is now.

 

Does that have to be done at a honda dealer or can another dealer do that as well

 

Just unplug the negative battery cable and let it sit for a few minutes to reset the PCM to default values.

 

THE REAR SENSOR IS A FUEL RATIO SENSOR MONTORING AIR FUEL RATIO AND KEEPING IT AT THE CORRECT RATIO ALSO THE AIR INSTAKE SEMP SENSOR WILL ADJUST TO THE CURRENT CONDITIONS. NO NEED TO DO A RELEARN ON THE PCM IT WILL MONITOR THE VALUES AND MAKE THE CORRECTIONS.

 

Turn your caps off...

No it isn't, that second O2 is there to simply monitor the efficiency of the catalyst. Unplug it, and you will throw a code P0420 Catalyst efficiency below threshold.

PCM's do not like drastic changes, and if it all of a sudden sees more air than fuel and changes it's Long/Short term fuel trims it will set a code, most likely system too rich/lean.

The modifications the IAT makes to fuel trim is very minute, and serves only as a fine tune element. Combustion misfire/efficiency and Primary O2 readings are the biggest things that affect fuel trims, timing will also adjust as well to correct any poor combustion.

 

put back the rear o2

 

I would leave the car alone. Put the sensor and your stock intake back in the vehicle. If the cold air intake inlet is inside the engine compartment, it draws in hot underhood air. If your stuff the inlet down through the front of the body it becomes a cold WATER intake. I have repaired a few cars already because of hydrolocking due to cold water intakes. It was expensive for the customer.