So I made an ALDL->Serial Cable this weekend and came across something that blew my mind and I cannot think of a cause or solution.

Keep in mind, this is for a '165 ECM on an '87 GTA.

My BLM readings are around 144, yet I'm running rich? Extremely rich. Failed emissions by 10-fold.

I'm not sure if it's that it was in ALDL mode that would cause that reading, however I disconnected the 10k resistor and it was still reading 144.

The MAF reading also seemed low - 23g/s...

Possibly a defective ECU? I'm trying to upgrade to a '730 MAP asap.

 

The only times that happened to me, the O2 sensor was bad. I put in a heated one and it never happened again.

 

Would it be dependent on whether or not it was/wasn't in closed loop? At the time in wasn't in closed loop. (Hell, I don't even believe it goes into closed loop, so maybe it is a bad 02.)

 

I just noticed that MAF reading. If it is 23 gps at idle, that is double what I'd expect. Not sure what you have going on.

 

Don't take my word on that measurement, I could be wrong. I don't have the logs with me with me at the moment.

But looking at the bin files, 23 g/sec seems to be stock in the ARAP been if I'm reading it correctly.

But intermittent misfires don't help at all, hah. Maybe going Carb would be easier. Nahh, this tuning stuff is too much fun.