I hit a deer with my 04 Saturn ion and had a exact replica with a bad motor so long story short I made 2 cars out of one now my predicament has started because I have a 04 Saturn that only needs a few new front end pieces and to rebuild the motor (mind you I don’t want to get rid of this car everything works perfect on it and I even undercoated the car a few years after I bought it) and the motor has been laying in the corner of my shop for about 2 years now waiting for me to come up with an idea to tune the car now iv recently got the idea to run original ECM and drop off the ICM and the fuel injectors and then run a a full stand alone to run the ICM and injectors and piggy bank off other sensor and add sensors as needed and after searching for awhile I found 1 person talking about it but they had basically said it’s kind of a waste of time due to it only being a half tune (I’m not sure how I feel about it currently I feel like he was talking about just a piggy back system in general where as I’d do a full stand alone where the factory ECM is the piggy bank so the BCM still functions properly) but i am curious after all this time is the only real way to tune this car and keep factory functioning buy stealing both cavalier or cobalt pcm and bcm and tuning those and then hardwiring the EPS up to work with key on or have I over looked an extremely easy option I haven’t found yet I already have to build this motor but instead of just doing bearings I’d love to go all out with pistons rods heads and boost it (I love the sound of the supercharger) and put it in my nice car I mean my biggest thing is everyone says sell it buy a redline but I already own this car and love it and redlines are either rusted out or 8k for just the car anymore

 

I tried to read this and make some sense out of it, but without punctuation marks, I don't have a clue as to what the hell you're talking about.

 

[QUOTE=Rubehayseed;71819]

basically, I am asking why couldn’t someone do a stand alone harness. Then use the original harness as the piggy back to make the BCM work properly and keep it fully functioning. Like, using haltech or Holley to run the motor but splice the original ecm into the functional parts like starting the car, speedometer, rpm, abs, a/c, things like that.

 

SBR performance might be able to help.

 

I did look into them and contacted them. Sadly it looks like all there products are for the caviler that runs a pcm, at the end of the day I might have to bite the bullet. I might end up building the motor and trying my idea, who knows maybe I’ll make some good money making a YouTube video of it. If it actually works. Ik there are tons of people that want to boost there 2.2 ions if it doesn’t work the worst that can happen is I have to find a new and rewrite my BCM, or go full blown race car with Manuel windows and no a/c

 

@DropDead ?

 

what does that mean?

 

Requesting input of our resident ion specialist

 

Okay, I don't have enough experience with today's modern vehicles to answer your questions. I'm an old fart, old school backyard, shade tree man with a preference for vintage automobiles. I do all of my own wrench pulling, but don't know enough about the individual computer controlled systems to help. DropDead is our young gun who knows about this type of challenge. Hopefully he will be able to help you. I'm out.

 

It's a big project if you're willing to take it on.
I have not personally done a stand alone, yet. It's potentially in the works.
I do have a buddy that ran I believe it was a halltech stand alone system for engine management. Wired it to the engine, went to the dash/programmer thing it came with. Left the stock ECU in place for body functions. I'm not 100% on how he wired the halltech to the stock ECU so the car would wake up on key cycle. He did still have a functioning ignition.
It's very possible to do. He's not active in any forums or even Facebook anymore.
He was in a 2.2/2.0 turbo hybrid build.
If you're good with wiring and schematics, I'd do it if finances allow.

I'm currently lsj turbo swapping a sedan. I'm going the stock route though of using an lsj PCM/bcm/cluster/engine harness/dash harness/body harness. That's the plan for now though. As I'd like to make it look like it came from the factory with an lsj.
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