I have a 95 P30 Step van with a v6, and A 94 HD 30 Chevy Van 454 that is on propane for a donor. Both have 4L80e transmissions and looks like a direct easy bolt it with near all the same wiring to the engine sensors etc,

The HD 30 Was a fleet vehicle converted to propane only. Mixer mounted on the top half of the TBI retaining the IAC TBS sensors. looks like all the other wiring is the same as the V6 to the distributor and EGR Coolant sensor, except different style units and vacuum controls located elsewhere,..... except looks like no Knock sensor on the 454.

The HD 30 computer, # 16196395 *86BHDKK533144559* is mounted under the drivers seat of the regular van cab.

It also has an Autotronic dual curve fuel management module on the firewall, but looks like it hasn't been used for years and has no wiring harness to it or traces of hacking anywhere else. So I don't know if the Computer has a chip in it for it to operate without gasoline and to operate the transmission or the transmission has been modified to work without the computer.

95 Utilimaster Step Van, I'd like to swap this into the V6 Van and initially hook up to gasoline. not expecting too much problems with getting the fuel lines to match up. And hoping the top of the TBI is the same as the V6 TBI of which I have a spare top half for and V6 injectors... but know the 454 TBI has a larger bore.....or just find another at the wrecker.... (I'm thinking running on smaller injectors might be more economical? and not sure the V6 is running properly now, at idle looks like way to much fuel spraying on the closed throttle plates and is pig on fuel for anything other than highway driving..)

I haven't been able to find the ALDL terminal in this yet. but can see the computer easy on a ledge behind the fuse box on the side of the dash standing beside it with the door open.
Sometimes the check engine light comes on, but goes off when restarting..most of the time and possibly relative to how long turned off. like more than a few seconds....

Looking up the 454 computer # brought me to this forum, I have no idea about programming ecu's and use a Mac.
Some info elsewhere suggested the V6 and 454 might use the same computer, but somewhere in this site it suggested there could be problems trying to run the 454 off the V6 Computer regardless of being the same.
I'm speculating the 454's computer will fit the V6's harness, but will have to take the dash apart to get at it, And or wondering if I should swap harness's
As the 454 doesn't appear to have a knock sensor and seeing reports some don't. The V6 harness not much different and not needing one hooked up anyway for the 454 and using the 454 computer....??

With no extra wiring on the HD 30, Would the computer be hacked or have a prom in it to run on propane and easy to replace with ???
As previously noted, has to have had something in it to make the transmission work.

Any suggestions on how this will work and what other problems might come up or verify what needs to be looked at, changed. before I start turning bolts.
I don't own it quite yet, it's not going anywhere soon, the owner is using it for storage and planning on taking the box and power tailgate off and scrapping it...and will likely let me open up the ECU to what's in it before committing to take it..or take it anyway at the price it's being offered and resell it. Can take everything including the transmission. Just the radiator is shot, (so also doing a compression test before installing).

After I get into it and running on Gas, I'll likely be looking to convert back to propane or dual fuel, wood gas and looking for another management system anyway, seeing there no support for the Autotronics and don't know if it was working anyway, not having any harness for it.

Thanks for your inputs. bobx.

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