Is there a chart or tutorial out there that gives the definition of these values and the correct range for them? I've been searching the board with no luck.

Some questions:

1. What does BLM mean? I've been able to find that it should be at 128 and it deals with the rich/lean of fuel. But whats does BLM stand for though?

2. The reason I started this project is because I have a very low Idle when warm. When datalogging, the idle shows 500-525 but I need 600. I've noticed that the TPS voltage is -.3 at idle. Is this supposed to be negative?

Basically I just need the range of the values and what they represent.

 

Doing some more research, I've read that the TPS should be a .54 at idle. Is this correct? Guess I'll have to try adjusting it.

Here is the datalog that I got: Click me

 

BLM stands for Block Learn Multiplier. It is the long term fuel trim. Your '91 TBI ECM has 16 cells in a 4x4 matrix. Above 128 and the ECM is adding fuel (lean engine AFR from O2 sensor), below 128 means the ECM is removing fuel. Below 128 is common when CCP is active.

Yes, the TPS should be at .54 volts. However, on that ECM anything between 0.40 and 0.70 works. It auto zeros.

RBob.

 

What do you mean that it auto zeros? The reading of -.3 was what I got from the ECM when datalogging.

 

bump

still looking for an interpretation of the values. What are the correct values for the O2, IAC and everthing else the program gives?

 

Do a lot of research over on DIY Prom.