I am in the process of installing a series II (complete cradle) into my "Winnebago, LeSharo motorhome". Originally, it was a Renault 4 cyl diesel FWD. I purchased a 98 Bonneville as a "donor" car. I have all the "mechanics" of the process under control, but, it took me 2 days just to remove the dash and wiring harness from the Bonneville. BOY!!!!, that Pontiac has a lot of wiring!!!!!!....and component modules!!! My question is...HOW MUCH OF THE ELECTRONICS DO I REALLY NEED FOR THE ENGINE TO RUN ONCE I GET IT "BOLTED" INTO THE OTHER CHASSIS? I certainly understand the need for the main computer in the front left of the engine compartment. But, what about the "body control module", the "anti theft module", "headlight control module", etc? And, what is that "u" shaped ceramic thing out there on a wire by itself?.....and what'* that "green plastic" thing about the same size out by itself up under the dash? Wiring diagrams are great, but, they don't tell me what I can get rid of.
Any answers are greatly appreciated.

David McCullers
davidmccullers@yahoo.com
817-223-1578

Welcome to the forum!

what kind of trans are you going to use, you are going to have to get someone who knows what there doing to take the emissions, security and all that out of the computer, then you wont have to worry about it. what you do with the trans is going to matter too.

Welcome to the GMForum.com. Not a 3800 owner myself but we have a good gearhead crew who can help. It'* a little slow here Saturdays, but I'm sure some will be in to help w/ your problems. I copied your post to "General Chat" as well for better visibility since we don't have a "Winnebago" Section. hehehe

But I think it'* awesome to have one powered w/ a 3800.

Welcome to the forum! You should post up some pics when you complete the swap! It sounds like a very interesting project.

welcome

Moved to the correct area.

I would say for sure you will need the body control module, as well as the antitheft. But I can't say for sure. Billboost may be able to answer this better. The rest should be able to be removed. Your also going to need to look at the transmission if that'* not original. The PCM may throw some codes. So you may need to do some tuning.

Can't do much about the tranny. It'* the 4t65e, I think. I did replace the 1-2 and 3-4 solenoids while I had it out because that what the code called for (took the Bonneville to a tranny shop before commencing changover). I checked the old ones with an ohm meter though, and they were both OK. I hope it shifts OK when I get it going.
I was hoping to get it started today, Thanksgiving, but, I put "juice" to it briefly, late yesterday, and got nothing.

David
Le Sharo 3800 conversion

If it is going to have the BCM and the VATS, I'll have to buy another donor car, as I have removed the modules and all the wiring from them back into the harness as far as possible.
This is making me long for the good old days when you could just drop an engine into a race car and hook up a battery and an ignition switch and go.

D

This may help you bypass the VATS. https://www.gmforum.com/electrical-133/bypass-vats-92-99-a-279119/ Are you getting any power to the starter? The VATs wont prevent cranking, it will start and then shut down the injectors. Something that comes to mind is the neutral safety on the transmission. If this is not working it will prevent any cranking. The engine should start out of the car, but all conditions need to be met first.