Last night I found a couple of things really annoying while driving around with the ECM in ALDL mode.

The idle speed was high (I know it's supposed to be 1000, but my tach said something like 1200), and just about the worst thing about it is that when I would not be in Park or Neutral and brake to a halt, the IAC would start opening up (I hear pronounced hissing begin to increase) and the engine would start revving up to the point where I become worried about my torque converter.

It would sometimes get to the point where rear wheels would start spinning slowly in place because the rear brakes would start giving up -- so then I put it in N and find the engine revved up to 2000 RPM. If I wait for 10 seconds the IAC starts closing and the revs drop to ~1000 RPM.

This does not happen when I am in normal mode, just when I put the ECM in ALDL mode. I know about the idle speed, but is this IAC bs normal?

On the WinALDL page I read that simply not putting 10kohm across A and B makes some ECMs put the data out but saves you the ALDL mode wierdness. I don't think my ECM outputs anything without 10kohm across A&B. Another thing I am going to try later is put 20kohm across.

Also if I see the Rich flag on in closed loop, I should assume that my fuel map tables are way off?

Is there patches to null this cr@ppy behavior?

 

Just leave A&B open. The '8746 will still output the same data stream.

RBob.

 

Allright, thanks! Is there a place where I can buy the ALDL connector?

It's a bit impractical to shove wires in there every time + they sometimes drop out while driving around. I am sure someone asked that before, but the search is off right now...

 

Tough to get the connector. Summit carries the Auto X-Ray cable for not too much. Just change the end to fit your laptop.

Or can wire in a DB-9 parallel to the ALDL connector and make the cable to fit.

RBob.

 

I just looked it up -- $28 for the connector is a bit too much for me, so I'll just splice the wires in and have the DB-9 in the car permanently.

 

I took the two wires coming off the serial cable and covered them in solder. Then I hammered them flat to fit in the ALDL connector. This way they fit tightly and do not fray when you try to put them in.