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SWAPping problems (incompatible car)

PostPosted:May 27th, 2024, 10:09 pm
by El Vasao
Hello guys.

Disclaimer: I'm not 300M owner. I just found your forum while trying to find solution for my problem. Dear moderators, don't push me plz if I've been created topic in wrong section.

To start, my name is Vasily and I'm from Moscow, Russia. Sorry for my bad English, I'll try to do my best while explaining my problem.
I decided to use 3.5 EGG engine (300M) and A7222702100 (300C) transmission for swapping into my (youngtimer?) GAZ-24.

My previous swap to this car wasn't so complicated - it was 2.4EDZ and M/T, no PCI BUS, no CAN-BUS, very easy.
But, if we talk about 3.5 EGG there're some problems.

As I understood, PCI BUS in 300M is a kinda 1850VPW which used to communicate control modules with each other.

So, first question - what's the PCI BUS function?
The second one - which additional modules (body computer, dashboard) I must connect to run 3.5EGG with P04896732AB ECU in case I'll be able to disable sentry key (immobilizer) system?

Waiting forward for your answers.

P.S. Picture for attracking attention.
photo_2024-05-28_06-06-35.jpg

Re: SWAPping problems (incompatible car)

PostPosted:May 28th, 2024, 12:33 am
by LUNAT1C
Sounds like you have quite a Frankenstein project going there. Hope you let us know how it all goes.

PCI bus (as well as CAN bus from 300C) is a communication network between each of the modules of the car to perform various functions. If I understand right, the PCM and the BCM are the most important controllers in the system, as they take information from all of the other controllers in the car and then send instructions back to start/stop/adjust whatever the function is in the moment. PCM control the engine and transaxle, BCM controls non-power train functions (heated seats, memory seats, power windows, HVAC, etc.). There might be some communication between the two for displaying information in the instrument cluster and the overheard vehicle information center, I’m not sure.

Couple things… 300M uses PCI bus. 300C uses CAN bus. They are not the same, and are not compatible. When you say 300C transmission, I assume you mean the 42RLE RWD version of the 300Ms 4-speed automatic? In the US, all 2005-2010 300Cs were V8s with the NAG-1 5-speed automatic, but I’ve been told some Euro market 300Cs also had the V6 and 4-speed. If it’s the 5-speed you’re referring to you might want to rethink your plan. I don’t believe the NAG-1 mates up to the LH-platform 3.5L V6. No compatibility mechanically or electronically that I am aware of. Maybe someone else has better information.

For the second question, I don’t know what vehicle that ECU part number pertains to. If that is an LX car (Charger, 300C, Magnum) PCM, it won’t work on the LH car (1998-2004 EGG) without a lot of sensor and wire harness changes. If you’re looking for a way to run the LH 3.5 without the immobilizer system, you’ll want to locate an LH car with 3.5 and no SKIM. The standard output cars came that way, in the 02-04 Intrepid SXT and possibly Concorde LX optioned with that engine (some came with the 2.7L V6). I’m not sure if the High Output cars ever did.

If your goal is to put a RWD Chrysler V6 power train into the GAZ, I think the best way to do it without spinning your wheels trying troubleshoot a multitude of compatibility problems is to take the engine, transmission, PCM, BCM, sensors, harnesses, etc. all from the LX car. The electronics between the two vehicle platforms just don’t like each other at all.

Re: SWAPping problems (incompatible car)

PostPosted:May 28th, 2024, 4:20 am
by El Vasao
LUNAT1C wrote:Sounds like you have quite a Frankenstein project going there. Hope you let us know how it all goes.
As usual...)
LUNAT1C wrote:PCI bus (as well as CAN bus from 300C) is a communication network between each of the modules of the car to perform various functions. If I understand right, the PCM and the BCM are the most important controllers in the system, as they take information from all of the other controllers in the car and then send instructions back to start/stop/adjust whatever the function is in the moment. PCM control the engine and transaxle, BCM controls non-power train functions (heated seats, memory seats, power windows, HVAC, etc.). There might be some communication between the two for displaying information in the instrument cluster and the overheard vehicle information center, I’m not sure.
Yes, I understand functions of PCI/CAN bus. But, accordingly to this:
https://www.kolhosniki.ru/mitchell&mark ... =A00154285
PCI bus connection between PCM and BCM is necessary only for (as I understood) sentry key, "comfort" functions (AC, Dashboard) and maybe some ABS. So, the main point of my thread: Is it possible to start engine without PCI BUS connection between PCM and BCM in case when sentry key system is disabled? (I can flash PCM to remove this system)
LUNAT1C wrote:I assume you mean the 42RLE RWD version of the 300Ms 4-speed automatic?
Sure.
LUNAT1C wrote:I don’t know what vehicle that ECU part number pertains to.
Looks like it's the "Last generation" of 300M, where ECU and TCM were implemented in one module: https://www.ebay.com/itm/235151368508
So, it's LX. LH is too complicated, so I decided to use LX PCM.
LUNAT1C wrote:If your goal is to put a RWD Chrysler V6 power train into the GAZ, I think the best way to do it without spinning your wheels trying troubleshoot a multitude of compatibility problems is to take the engine, transmission, PCM, BCM, sensors, harnesses, etc. all from the LX car.
No way. I'll make my own custom can-line, I don't need all LX electricity:) I still can use custom ECU and TCM, but I don't want to spend the entire life while tuning it.

Thank a lot for your reply!

Re: SWAPping problems (incompatible car)

PostPosted:May 28th, 2024, 9:21 am
by rustybronco
(I can flash PCM to remove this system)
What software/ device are you using to remove the sentry function?

Re: SWAPping problems (incompatible car)

PostPosted:May 29th, 2024, 7:05 am
by El Vasao
rustybronco wrote: May 28th, 2024, 9:21 am
(I can flash PCM to remove this system)
What software/ device are you using to remove the sentry function?
Idk. For this I usually search for self-employed technicians in the bulletin boards in the Internet. I found one, he will remove sentry key for 3k roubles (approx. 30$). I know that for 300M they flash 93c76 chip in PCM.

Re: SWAPping problems (incompatible car)

PostPosted:May 29th, 2024, 7:44 am
by FIREM
Interesting project to say the least. There is/was a guy that swapped a 3.5 into a Pontiac Fiero years ago.
viewtopic.php?t=30992
I guess someone has to be the first to attempt something. Hope it goes well and you see it thru. Please do keep us apprised of your progress.
Today almost any one can do a LS or HEMI swap with the proliferation of kits available, but someone had to do it first.

Re: SWAPping problems (incompatible car)

PostPosted:July 1st, 2024, 8:16 am
by MoPar~Guy
I would go this route if I was installing a modern engine in an old car:

https://speeduino.com/home/