No ALDL connection with 93 LT1 $DA3

Wondering if the ecm is bad at the pin or somewhere else internally? Or if the adx file on this site needs edited to work? I have searched around and it seems there can be issues connecting to these computers.

Car is a 93 fbody lt1. Has mild cam and full exhaust so it needs a tune. It did have a hypertech stage 2 chip in it and did seem to run ok but rich at cold start. I was able to burn a chip using a slightly modified bin from the $DA3 thread here, i believe a BDZL bin. Car runs on it so ecm seems fine but i cannot get the aldl to work to log using tunerpro rt and moates cable.

first off this isnt my first time, i have tuned many tpi cars, some tbi trucks and other 94-95 lt1’s as well as 96-97’s using jet dst. My cable connects fine to other cars. I have a spare tpi 730 ecm here i hooked to battery and connected fine to verify my cable works last night.

we tested the aldl port wiring all way to ecm connector and it is fine. I pulled ecm and put it on the bench with battery connected to the power and ground pins and pinned my cable to the aldl stream pin. Tried everything i could and nothing connects. I let it try the $da3 adx for 5 min and never gets thru. I tried tunerpro version 4 with a $da2 ads and nothing.

what else can i do? Thanks

Have you tried running DataCat, even as a trial version, to see if it would connect successfully? That'd be my first thought, if you don't have another scan tool around to test connectivity with.

I just downloaded and attempted. Never used this before so browsed thru it for 15 min and i think i set it up right and tried to connect but i dont think it did. I tried grabbing dtc using the get dtc operation and it said operation failed. So i dont think it worked either

That points to a problem with this particular car, unfortunately. DataCat should absolutely connect to a $DA3 or $DA2 car without any issues. If it's not the program and it's not the cable, there's something up with this particular car. Unfortunately as I don't personally own a $DA2 or $DA3 car I can't help with any more in-depth diagnostics.

I’ll try it again to be sure but the ecm is out of the car right now on my table with power and grounds connected. Nothing with the car is associated with this so its an ecm problem if not any of my doing with this DataCat or tunerpro rt

had same issues with DA2/DA3 ECM's, even Snap-on and Tech2 had issues. It was swap engine. For me solution was to add extra grounds and fix issue with one ECM Ignition swithed +12V.

best regards

Hiya, it's been a long time since I had one of those in front of me but it seems like you also need to tie the analog ground with the ECM grounds for data to clean up. Also need 12v switched and not hooked at same time as ECM BATT pins, meaning, use a switch to turn on the ecm ign pin.

Using DataCat there is a cable test function. Test VCI.

It says my latency timer is 16 ms and will cause ecm comm issues. Use device manager to set interface advanced port settings latency timer to 1 ms.

I gotta figure out how to do that now

Well that didnt work. So looks like this Ecm is either Bad or the aldl pin d4 is just bad

looks like we will have to tune blind with just the wideband and take mental note of rpm and maybe try hook up a vacuum gauge to get approx kpa readings

fun stuff

That will be a huge pain. If you've tried all the wiring to be had, one last thing is to burn a bone stock file to the chip. Over the years I have seen plenty of times a file gets corrupted and the aldl goes fubar. Most of the time with emulation weirdness. Otherwise take that thing apart and fix it :D

p.s. I think those things look like a 7427, are they? Rockauto shows them in stock.

Burned the chip twice and also with a hypertech that came in the car it did not connect. I’ll try again but the car ran ok on the chip i burned so i doubt it was a chip

i guess i could try with the stock memcal/chip in without the moates adapter too.

We are just gonna tune it by wideband like many have done with carb cars in the past lol

I remember ya bro and I know you know what you're doing. I was just offering up some crapola :happy:

Quote:

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Originally Posted by In-Tech

I remember ya bro and I know you know what you're doing. I was just offering up some crapola :happy:

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I know I appreciate any thoughts. I tried with stock chip again and nothing. I remember your screen name too btw lol