Ok here is the deal. The ECU had no codes.
So I did the following:
Checked battery voltage, 12.89v off and 14.39v car on.
Connected my AEM wide band o2 kit to the exhaust, and started the car.
WB- 16.2 AFR open loop / idle
WB- 16.6 AFR closed loop / idle
1200 RPM cold, down to 1000 RPM warmed up on all 6 plug wires (multi meter)
PF starts to stumble in park.
Using my digital multi meter at the ecu:
MAF Signal 1.103v / idle
MAF Signal 1.7v / light rev
O2 heater (-0.514v) (pin 106)
O2 signal (-0.262v) (pin 19)
O2 signal 0.214v heavy revving (pin 19)
Driving in my drive way, which is long enough to test a few things, the car was now smooth. My WB read 13.0 AFR in closed loop at WOT up to 30mph as I had to hit the brakes to slow down.
I did notice this odd thing, my WB was a steady 15.8AFR which equal to (-0.333v) at idle, 990-1000 rpm. What is this? Is my o2 going bad?
The ECU I have looks to be new. In any case the numbers on it are: H9 MECM-V260 A1 4831, if that means anything:
Also one last thing, I did notice a loose plug. It’s a blue with white plug, with female pins on it.
Colors are:
Orange White / Pink
Black / empty
Any ideal?
Thanks a bunch.
Tony