Hondata

Okay,

Here's my new problem.. I just switched to a p28 ecu for my s300..

I was using a chipped po6 before and had no problems switching from open loop to closed loop. I am using an Innovative LM1 and have the analog signal hooked up to the ecu inputs for the o2 sensor. and also to the EGR valve input location for datalogging on the s300.

Now w/ this p28, when i switch to closed loop, the engine leans out to about 19-20 afr and is on the verge of stalling out. when its in open loop, it will idle normally around 14.5-15.7 afr.. I have to unselect the option immediately, else it will stall out.

I have to add about 22% fuel to the over all fuel trim for it to idle normally in closed loop. But by doing this, it affected the open loop afr's, making it dip into the 11's at idle.. So for now, I am stuck driving the car in open loop, which doesn't really bother me.. I"m just curious why this is happening w/ this p28 and not on the p06.. I'm not getting any CEL's either..

Here's a datalog and bin file of this problem..

It sounds like you have the wideband signal input into the O2 sensor and the narrowband signal input into the EGRL input. This is backwards.

I didn't change anything on the ecu harness, ie move the wiring around.. The only thing i swapped out was the ECU's.. Unless the p06 and p28 have different pinouts for the sensors..

I"ll have to get a ecm diagram for a p28.. I also noticed that my 02 voltage stays around 3.85V..

Nonetheless, I will check that out too though.. thanks..

These appear to be false readings from the wideband as you can see by the fact that when it reads rich, the duty cycle is not changing. I suspec a problem with the input your are using, or there is a problem with the signal the wideband it outputting. Check the wideband output with a multimeter with it not hooked up to the ecu.