I swapped the 4.3 in my 97 Chevy chenne with a 5.7 out of a 99 Chevy surburban 4x4 switched engine wiring harness too got it to start but dies in a sec or 2 what did I do wrong
Is this a good question?
Rep: 419
4
Gotta swap everything, like computers, Body Control Module, immobilizer, keys, all those things at the same time (not everything is included in engine wiring harness). Even back in 1997, those things had over-current protection on pretty much every circuit, so will shut down after a brief start. Pretty much every model coming out at about that time, they changed things around, changed the spec's, etc. I don't think you killed anything, but you need to keep every box, every module with the engine when you swap... and they love to hide those things where nobody looks! Older vehicles didn't have such smarts and we could just swap engines and expect things to work with slight adjustments. Get hold of the full diagram and check every single thing was included in that harness, right down to injectors.
Was this answer helpful?
@automotive just out of curiosity. Can those module be reprogrammed to fit the current application or are they firmware tied to the particular model they come out off?
Yes & no. Those particular ones probably can be done by an experienced hacker with some mods. The later ones are much more difficult (code-hopping & code-rolling), but I did briefly meet with someone whose boss bought him the expensive equipment to do it and he was quite successful. Some modules don't run software that can just be reprogrammed, but with a lot of time and effort, these can be traced through and replicated, often with something far better. I'm a big advocate for using GaN switching components.
@automotive I figured something like that. Gone are the days of simple engine swapping :-) Thanks for the info.
Past 24 Hours: 0
Past 7 Days: 0
Past 30 Days: 5
All Time: 70
3 Comments
Are you sure you're getting enough fuel?
by brandon k
Well I don't know cuz now I turn key an I get nothing no dash lights nothing kind of thinking it might be ignition
by Brett
Unless an expert with wiring can figure this out, you may be better served searching for Chevy forums with members familiar with your engines, wiring swap and specific problems. There are many questions to ask, to narrow this problem down related to; factory security, fuel pump, fuel pressure, ignition system, throttle body or EFI system, etc.
by F Dryer