Which P4 PCM should I use

[CDeeZ]

From one of my other threads:

Well the conversion is done but the truck idles like crap. Haven't even tried to drive it since it idles so rough.

I CAN'T connect to the PCM with my laptop now that I've done the conversion... I tested with a 6395 PCM, and loaded the .xdf and .adx files from the 6395 thread onto my laptop but still got nothing when trying to scan....

What am I doing wrong here? Why can't I connect to the PCM to scan with my laptop????

Am I not doing something right on the scanning for error codes? Did I screw up some pins when swapping them?

I also posted in another thread about 3 remaining wires I had from the pinover... Crank signal, A/T high gear switch, and the knock sensor wire from B7 on the 747 ECM... I'm pretty sure I just leave the crank signal, and A/T high gear switch unplugged, but what do I do with the wire from the knock sensor???

My new knock sensor should be here late today or maybe tomorrow, so that part isn't done YET, but I can't see that not having a knock sensor hooked up would cause it to run this bad? The ESC is still connected. I know I need to bypass it, but is that my issue here? I know in the conversion thread it says "(3*)= B.) Wire like 1995 C10 Truck, Bypass ESC (Blue to Brown) and useLate TBI/TPI 305/350 Knock sensor" But what does this mean?? Do you simply hook the blue wire into the brown wire at the ESC (Bypassing it), and what about that knock sensor wire from B7????

And finally, can someone tell me what this means from the 747 to 427 thread:"I would also like to mention that the orange Serial Data wire needs to berelocated from the top row, Pin "E" to the lower row, Pin "M". You will alsoneed to scan the vehicle like a 1993-1995 G-Series Van, C-Series Truck,S-Series Blazer, etc with Auto transmission."

Why can't I connect to scan with my laptop!?!?!?!?

EDIT: well I think I figured out why I can't connect to scan... I need to move my serial data from pin E, to pin M on the ALDL port... Sorry for overthinking this one guys! But can anyone else help me with my other questions regarding the 3 wires? And about that ESC bypass..... Just blue to brown and late TBI knock sensor, I understand that, but what about the wire from B7?!?!?!

[EagleMark]

Crank wire is not needed on 97427 PCM.

And finally, can someone tell me what this means from the 747 to 427 thread:"I would also like to mention that the orange Serial Data wire needs to berelocated from the top row, Pin "E" to the lower row, Pin "M". You will alsoneed to scan the vehicle like a 1993-1995 G-Series Van, C-Series Truck,S-Series Blazer, etc with Auto transmission."

That's why no data! I answered that in other thread.

[CDeeZ]

Well I moved the orange serial data wire to pin M. Still nothing when trying to scan............... Now what?

Help me out here guys please. This is my only means of transportation and I'm going to need it in the next couple of days, I'd like to at least get it where it runs decent on the 427 W/O being in limp mode or throwing tons of codes.....

And about the wire from knock sensor wire from B7.... does it remain unhooked from the PCM?????

[EagleMark]

Turn the key on without starting the engine and watch the check engine light. It should comeon, blink and stay on steady. If not there is an issue.

[JeepsAndGuns]

Yes, what is the check engine light doing? Is it blinking really fast? I know there has been a couple times and I goofed up and either didnt get a chip in place correctly, or forgot to put it in at all (lol) and it would start and run, but run like crap, check engine light blinked like crazy when I turned on the key, and stayed on when running. I also could not get aldl connection when it was running like that.

[Six_Shooter]

There's no such thing as a "good dizzy".

[dave w]

Only three wires are needed to the ALDL connector on the '427 PCM conversion. Pins M, A, and B. Remove the others and make electrically safe by covering the exposed ends with heat shrink.

Elimante the Knock Retard and ESC Error Code in the PROM Programming and don't worry about the knock sensor wiring for now.

I triple check the pin wiring to the new PCM, get just one pin wrong and that's no fun!

dave w

[EagleMark]

There's no such thing as a "good dizzy".

Ouch...

[CDeeZ]

Key on, engine off, CEL comes ON, goes OFF, and STAYS ON.


Three wires. Okay. Maybe that is why I couldn't scan with laptop?? I'm going out to eliminate other wires after I post here and grab some bins.


I have double checked the pin positions and they're good. I will do away with the ESC stuff at least until I can get this PCM to act right.


My G1 adapter from Moates came in the mail today so I can do some custom bins now for the 427
I'm going to just try a 5.7L A/T bin for now.

[CDeeZ]

Welp I removed all wires from ALDL port except M, A, and B. Still can't connect with laptop to scan... It's been a while since I set up my baud, com ports etc so I'm a lil rusty... Am I not able to connect b/c TPRT is still set up for the old 747 at 160 baud? How do you change that for the new 8192 baud of the new PCM, I forget.

Also, with the G1 adapter installed, I get no CEL whatsoever and the truck cranks and just dies. What is the issue now?

EDIT: I was installing the PROM backwards. Before anybody gives me grief about this, let me just say that the PROM goes in the OPPOSITE direction in the ZIF as compared to the 747, so easy mistake to make. The G1 seems to work, CEL goes on, off, stays on before cranking, doesn't come on while engine is running. It runs very rough still. I have BJLH.bin running it, with knock retard disabled and 43 ESC error disabled..

I'm going to check the pins a third time but I know they're right.

Still can't figure out why I can't scan it though?

[CDeeZ]

I've checked the pins at least three times, they are right.

Does anyone know why I can't connect to scan when I could with the 747?

[Six_Shooter]

There's nothing to change in TP RT to go from 160 baud to 8192 baud. Just load the correct ADX.

Have you tested for cable connectivity in Tuner Pro Preferences? You may just not have the proper com port selected.

[CDeeZ]

Thank you, I finally got the laptop to connect to the PCM, probably wrong ADX... I was able to connect with "A218 Trans1 $0D TP5 v250.adx"...

I'm seeing a bunch of error codes... All A/T related... The history tables, and Monitors features in TPRT are not working for some reason like I'm use to seeing them when logging with the 747 ECM... Is there a more complete/better ADX I should be using? The History table is actually totally blank. Weird.

[dave w]

I've checked the pins at least three times, they are right.

Does anyone know why I can't connect to scan when I could with the 747?

Is there a chance you can use a different vehicle to check the ALDL communication with? I'm lucky, I have a test bench to verify ALDL communications. Maybe you have a neighbor who has an OBDI vehicle you can check to see if your ALDL communication is set up correctly?

dave w

[dave w]

Thank you, I finally got the laptop to connect to the PCM, probably wrong ADX... I was able to connect with "A218 Trans1 $0D TP5 v250.adx"...

I'm seeing a bunch of error codes... All A/T related... The history tables, and Monitors features in TPRT are not working for some reason like I'm use to seeing them when logging with the 747 ECM... Is there a more complete/better ADX I should be using? The History table is actually totally blank. Weird.

Try this .adx

dave w