Anybody here ever swap engines from, say, non-turbo to turbo? I am looking at the wiring harness, and thinking that providing different wiring would be unusually aggravating, and maybe the hardest part of the whole thing. Looked a bunch online, but I did not find much about it. I have never seen a car before that the wiring harness didn't come apart, but of course I don't usually mess with wiring harnesses on a daily driver all that much.

I didin't really mean to, but I bought 5 850s for an average of about $500 each. 4 of them I was able to drive. But it's just a matter of time before I start consolidating them into a smaller number of cars that are in better shape, ha ha.

Is there a way to get the wiring harness apart at the firewall? I cut one out of a parts car so I could think it over. It looks like it was all one piece when the car was built.

I love cutting and splicing, so don't be afraid to be truthful.

 

There is no plug at the firewall and you are in for a huge job - the turbo cars and the N/A cars have a completely different harness.

You can get schematics here but the pagination is all screwed up.

Volvo Wiring Diagrams

...Lee

 

You might try over on Volvospeed. It might be under a turbo conversion where people have taken out a NA harness and added and or replaced the harness to support the turbos added sensors.

 

That's kind of a fun read over there!

 

I recommend you read and then let it go. You will get pounded over there by even asking the question. It makes zero sense to go down that route.

 

There is definitely some resistance there. I figured the wiring would be what would make it hard, but apparently that is pretty easy. They were all complaining about the obvious stuff.

 

I haven't but this guy did; put a turbo engine harness (and engine) into an N/A; might learn something from his thread:
Successful 850 N/a To Turbo Swap....yes, It Does Run And Drive, Quite Well I Might Add! - Performance Modifications - Volvospeed Forums

BTW: you're not putting an N/A engine into a turbo car, are you?

 

Thanks for the link. He didn't really say much; plug and play, with a 5 speed. I did some looking at the schematics and it looks like the wiring harness could be unlpugged under the dash. With an automatic car, and both cars being OBDII compliant, it appears that wouldn't be necessary. The harnesses are all virtually identical. It may also not be totally possible. The shape of some of the plugs changed around 1996, if what I see on paper is to be believed.

As an aside, I put a 97 ECM in a 94 (turbo) and it ran just fine. So at least for all the years of interest the data being looked at doesn't change, even thought one is 4.3 and one is 4.4. The 94 apparently had 2 O2 sensors and the whole OBDII setup.

As far as putting an N/A engine into a turbo car, that looks a lot easier to me, because there's nothing extra that you'd need. You'd just need an 1996 or 97 N/A ECM.