Mark Uptergrove

Thanks for bearing with me, epic fail on my part. In my defense...who the heck makes 2 white wires power/ground and black the sending wire??? lol

Tuned Performance

iTrader: (92)

I do see the green box but I don't know what color wire you need to tap without seeing a schematic.

RBob

iTrader: (1)

Because the O2 heater has no polarity, the wires can be connected to power & ground either way. Although the black wire should have been purple, as that is the color GM uses the EFI harness for the O2 signal.

RBob.

Ronny

iTrader: (1)

Another tip that shows you are running off a correct .bin is key on engine off you should see a blink of the CE light then solld on. No blink says you are not running off the .bin.

Mark Uptergrove

Good info. Well, I still have something off. I can run the original al 24 pin chip (has the 400.bin on it). But when I go through the process of setting the chip type (512) erase successful, select bin, write, then verify- when I put that chip in the ecm it runs in I guess limp mode fast flashing service engine soon...crappy. what's odd is when I read the 28 pin chip it reads the same as when I read my original 24 pin (that has the 400.bin ) any thoughts?

Mark Uptergrove

I'm back in the saddle, got my issue resolved, do any of these need tweaking? I have a new 195F thermostat in it, ill have some log data shortly.

Tuned Performance

iTrader: (92)

The mv settings look normal

Ronny

iTrader: (1)

Your BPC is 156? What size injectors at what fuel pressure?

Mark Uptergrove

350 Injectors. Fuel pump is rated at 70psi but obviously it is regulated at the TBI

Ronny

iTrader: (1)

What fuel pressure? Are you using stock spring? If so you may want to buy I a spring next step stronger from "top down solutions".

Mark Uptergrove

Greetings again. I am at my wit's end. I have verified grounding, the purple wire back to the ecm, replaced the O2 sensor, and I still do not get any readings on the O2 while logging. DC voltage from the purple wire to the ecm is a constant 1.4V. could this be a ECM issue or is it possible that something is wrong in the programming disabling the O2? thanks guys

Mark Uptergrove

Is there anything in the bin that would set the ecm for open loop only operation?

RBob

iTrader: (1)

Check the tan wire to ECM pin D6, it is the O2 input ground. Without it there won't be a valid reading.

> and I still do not get any readings on the O2 while logging

What voltage is the ALDL reporting? If the sensor it dead or unplugged it should report about 450 mV. That is the default setting.

RBob.

Mark Uptergrove

I am on o2 sensor #2, so hopefully it is the tan ground. I know the ecm is grounded, I'll trace the tan wire out. Crossing fingers this is driving me nuts.

Tuned Performance

iTrader: (92)

457mv flat lined when engine is warm

Mark Uptergrove

Bingo..d6 is open...I cannot for the life of me find or trace out the end of this solid tan wire under the hood any places to check or...do I jus cut it and ground it?

RBob

iTrader: (1)

Most likely at the back of the passenger side cylinder head (between head and firewall). Some 3rd gens also had EFI system grounds on the back of the drivers side cylinder head.

RBob.

Mark Uptergrove

After o2 grounding.

Mark Uptergrove

Thanks for all the input guys. The tan wire went to never never land apparently so when I grounded it bam closed loop. I do have a question about putting a heated O2 back on. Will I be good grounding the 02 Sensor to the frame or do I have to run its ground to the D6 on the ECM? (which is now grounded and working with a single wire o2)

RBob

iTrader: (1)

With a three or four wire heated O2 sensor, the heater ground goes to the engine block (not the ECM).

RBob.