I have Definately Secured this Statement with several cars. I have been wondering why my car was running so rich and I managed to take apart and strip my whole harness to neaten up things a little bit and discovered this verry useful knowledge. :naughty
NOTE: Late model Blacktops (TYPE-X) use a different harness Layout then the two mentioned below. If you need a pinout for that harness please email me or post below.
ok here it goes:
Early Blacktop Harness' use a Brown/Yellow Stripe (pin 114) wire to give the Heated Oxygen Sensor a Ground/Internal Standpoint.
So the E5/E6 Ecu's (Early Blacktop Computer) is needed if you are using an Early Blacktop Harness!! Otherwise the Heated Oxygen Sensor will not complete the circuit and give a legitimate signal to the ECU (via pin 19)
Early Model Redtop Harness' use a black wire that is looped up by the Injectors and Iacv in the harness and shares a ground with them by a crimped union of ground wires that bolt to the Intake Manifold itself
So the E62/E63 Ecu's (Early Redtop Computer) is needed if you dont see any Brown/Yellow Stripe wire in your harness on pin 114 of the ECU Plug.
But you could use an E5/E6 Computer with a Redtop harness, because the harness is self-grounding.
So the verdict is that your Heated Oxygen Sensor WONT work if you have a Early Model Blacktop Harness and a E62/63 ECU. Because it doesnt have a ground to complete the circuit and send signal to the ecu.
The Heated Oxygen Sensor Plug comming from the harness if you put it facing you with the Hump (clip) on the top goes from left to right like this:
^ ............................^..................... ...^
(b/y or Blk) (White) (Differs)
You can test to see if your getting signal by letting the car warm up at idle and pop the hood. With the 02 Sensor Plugged in still, take your multimeter and set it in Volts DC and stick your red probe/lead in the middle wire through the back of the plug, you should be seeing somewhere between .3 to .9 (+/- a little bit) but no higher than 1 or no lower then 0.
When you rev the engine a little bit the voltage should bounce around more frequently (cycling voltage) within the specs I told you, this means its reading properly.
This will tell you if your 02 Sensor is sending proper signal out through the Middle (Thick White) wire. If its sending too HIGH, then you have an incompatible 02 sensor or its faulty. If you have none then you have your wires wrong...or possible faulty 02 sensor.
You can quickly test continuity in the 02 sensor itself by unplugging the sensor and probing the two outter prongs and by having your multimeter read in Ohms, you should see anywhere from 3-1,000 Ohms according to FSM.
I hope someone can give me some feedback if you read this. I am almost 100% sure about this because I have tested and tried this.
ALSO WHY WE RUN RICH?
Most of us have the 190 or 255 LPH walboro and it bumps up the fuel pressure at idle.... which is supposed to be 36 at idle with hose connected to the FPR......and if you unplug it it should read 44 accordingly to the FSM...
If you have a Fuel Pressure Gauge and notice it sits high (40 ish) at idle, you can also tag this on to the list of reasons why we run a little rich.
This can be avoided by re-setting your base fuel pressure with a Adjustable Fuel Pressure Regulator that can be purchased by any of our sponsors here at NICO or anywhere on the web (ebay,others)
Also the Scale for an oxygen sensor is :
closer to .0 is LEAN
closer to .9 is RICH