Things I learned today with my 16197427 ECM (LONG POST WARNING!)

[FSJ Guy]

Over the past 9-12 months, I have been preparing to install a TBI system on my Jeep. IN the past, I have reworked two other Jeeps and have had fun tuning them over the years. But it's been about 3-4 years since I last tuned one.

I acquired a '7747 ECM harness as a starter harness and reworked it to fit the 16197427 PCM which has faster datalogging ability as well as electronic transmission control capability. The harness has been re-pinned and ready to go for a while, now. I also added the required wiring and plugs for electronic timing control, Vehicle Speed Sensor (VSS) and a few other misc sensors not originally hooked up with the old ECM.

Fast forward to this weekend and I'm ready to start tuning. The harness is installed and hooked up, the AutoProm ready to go...

I plug in the AutoProm to my Windows 10 laptop and.... nothing.

Grrrrr.... Stupid Windoze doesn't come with a FTDI driver. Now, this laptop is NOT internet connected since I just use it for my VW's (VCDS, aka VAG-COM) and TunerPro. So I download the driver on my OTHER laptop, transfer it to the Windows machine, install it and finally have a working AutoProm.

I burn a chip (still remembered how to do that, at least...) and plug it in. The previous night I had already prepped and modified a stock 350 bin, adjusting the static timing, turning off EGR and setting it for a manual transmission to avoid error codes.

I fire it up and it idles semi-OK, but it DOES at least run. I can't get to rev up, however. It wants to backfire. I had not adjusted the electronic timing, yet, so I added 10 degrees of timing to both tables (idle and off-idle). Not a whole lot of difference. Then I notice that the SES light is NOT going out.

Next, I plug in a stock memcal and try running that. It runs and idles MUCH better. THAT doesn't make sense.....

I run a compare on the chip to make sure it burned correctly. Sure enough, it matches.

THEN I REMEMBER.... YOU HAVE TO LOAD THE BIN FILE INTO THE BUFFER FIRST!!!!!

D'oh!!!

I was burning random gibberish to the chip. Actually, it was amazing that it ran at all!!

So this time, now, I remembered to LOAD the bin into the buffer and THEN burn the chip. Amazingly, doing it the CORRECT way yielded MIUCH better results!!! Imagine that, huh?

Now on to DATA LOGGING....

I am trying in vain to connect. The AutoProm is connected, switches set up correctly, but there is no response to the gauges with the key on, engine not running. After too much time trying different (and wrong) AutoProm settings, I remember that on one of my conversions, Howell had switched the data lines on the pinout. The lines were swapped. So, I do a quick google image search and find that the 160 baud data line and the 8192 data lines are on different pins. A little work with a paperclip and the pins are switched and I have correct data streaming into my computer!

So, the takeaway to all of this is

a) ALWAYS READ THE DIRECTIONS (The software even told me that I had to load the bin into the buffer first....)

b) DOCUMENT your procedures. I referenced my OWN website (yes really) to check and see what things I had modified in the bin file)

c) Plan for things to take at least 2X, if not 3X longer than expected.

d) Nobody knows everything. This entire project would not have been possible without the collective knowledge and assistance of many, many people.

All in all, it was a successful day. I drove the Jeep out of the garage for the first time in several months, turned around and pulled it back into the garage. Now I'm off to adjust my timing tables! :- )

[shimniok]

Sweet! I reference my own websites all the time congrats

Sent from my XT1096 using Tapatalk

[babywag]

& that is exactly why I do like GM, and leave the initial timing in the chip @ 0* so if you're in limp home mode the thing is driveable!
So if you're ever in the boonies, and have some sort of problem it'll still run/drive well enough to limp somewhere.
When you alter the .bin and timing tables above 0* initial good luck with limp mode working.
Food for thought...

Is this on that stretch GW limo? That thing is sweet BTW.

[AwesomeJ10]

Using the harness that you got from me?

[FSJ Guy]

& that is exactly why I do like GM, and leave the initial timing in the chip @ 0* so if you're in limp home mode the thing is driveable!
So if you're ever in the boonies, and have some sort of problem it'll still run/drive well enough to limp somewhere.
When you alter the .bin and timing tables above 0* initial good luck with limp mode working.
Food for thought...

Is this on that stretch GW limo? That thing is sweet BTW.

Interesting reasoning about leaving the Initial Timing set to zero.... Hmmmm....

Yes, this is on the limo. It's the only FSJ I have, now.

[FSJ Guy]

Using the harness that you got from me?

Yes! Modified it to run the newer PCM. It was easier than messing with a used harness and having to thin it, IMHO.

[FSJ Guy]

Now I have to figure out why my BLM values are all stuck at 128.... :- /

[Grand_Wag_85]

a) ALWAYS READ THE DIRECTIONS

Glad I'm not the only one