Hello, all. I'm hoping someone here can help me with a lack of data problem.

As background, I have an '86 Vette which has been modified with new cam, intake, valvetrain, basically everything under the hood outside of the HVAC system. I was able to tune the car with an old (~1998) laptop and a direct connection from the ALDL wiring to a 9-pin serial connector. I would then modify the MEMCAL bin and write it to a Moates PROMinator (anyone remember those?). I was able to log data using TunerPro RT and work with someone to get a mail-order tune which was "good enough" for a while. Then my ECU shorted out (cracked insulation in the harness crossed some wires) and killed both the ECU and the PROMinator. So I replaced the ECU with another '165 and bought an AutoProm, which has a USB cable so I can use a more-current laptop.

However... now that I've decided to use this lockdown time to actually ACCOMPLISH something, and make the tune better than "good enough," I can no longer get anything from the ALDL port. I have:
-- checked the continuity of the data and ground wires from the ECU to the ALDL. They are fine.
-- checked that there is (variable) voltage leaving the ECU wiring harness and similar voltage available at the ALDL port. There is, and it's within the expected range.
-- swapped ECUs with a spare.
-- changed laptops and operating systems.
-- changed serial drivers after reading about issues with "newer" FT drivers, posted on this site.
-- used a simpler serial port monitoring program to look for any traffic at ALL.
-- tried every combination of dip switches on the back of the AutoProm.

What I see in TunerPro is... usually nothing. The real-time monitoring windows show no changes in bytes; I get whatever that memory has been initialized to (it's not 0's for some reason). OCCASIONALLY I'll get nonsense data, where for example my PROM ID will bounce between two different numbers, neither of which make any sense.

I've been running under the assumption that data should be flowing at 160 baud, which is standard for older 165's, and I'm using Mark Mansur's 160 ADX file with TunerPro. I guess there's a chance that it's actually 8192 bps, and I could try hacking an ADX for that unless someone has one I can use, but it's always been 160 baud in the past so I expect it to continue at that rate.

Have I missed anything you guys would consider obvious first or next steps? Does anyone have any other suggestions?

Thanks much
[RICHR]