3.8 to 5.0 Engine & Trans Swap NEED HELP!!

[Branton]

Hello,

I set out to swap out my 2012 3.8 sedan engine and trans with the 5.0 one. I purchased a donor car with the 5.0 engine and trans. So far, I've pulled the engine and trans out of both cars but cannot figure out a way to remove the wiring harness through the firewall so I can swap them.

It seems easy enough to fish them through the firewall on the drivers side but have no clue how to do it on the passenger side since the blower motor assembly is in the way.

Can anyone please help?!?!

 

[carguy75]

Hello,

I set out to swap out my 2012 3.8 sedan engine and trans with the 5.0 one. I purchased a donor car with the 5.0 engine and trans. So far, I've pulled the engine and trans out of both cars but cannot figure out a way to remove the wiring harness through the firewall so I can swap them.

It seems easy enough to fish them through the firewall on the drivers side but have no clue how to do it on the passenger side since the blower motor assembly is in the way.

Can anyone please help?!?!

Could you post several pics on the engine removal(wiring harness) from different angles to help us get a better idea of the situation?

 

[Branton]

Could you post several pics on the engine removal(wiring harness) from different angles to help us get a better idea of the situation?

Yes, thanks!

It seems like the blower unit is in the way from removing the harness. It’s the one I’m pointing to. Any input helps!

The clump of wires is what comes off the harness so I can’t pull them through, the area behind the blower isn’t large enough to fit the connectors, only the wire. I’m also pretty sure there are some clips holding it in place that I can’t get to without it’s removal.

Removing the harness in the drivers side seems easy enough.

I will post a walkthrough on here for anyone that wants to do the same job once I’m done and have figured it out, but for now…I’m stuck.

 

[carguy75]

Yes, thanks!

It seems like the blower unit is in the way from removing the harness. It’s the one I’m pointing to. Any input helps!

The clump of wires is what comes off the harness so I can’t pull them through, the area behind the blower isn’t large enough to fit the connectors, only the wire. I’m also pretty sure there are some clips holding it in place that I can’t get to without it’s removal.

Removing the harness in the drivers side seems easy enough.

I will post a walkthrough on here for anyone that wants to do the same job once I’m done and have figured it out, but for now…I’m stuck.

Just going by the pictures it does seem that the ac unit(blower unit) need to be removed to access the harness under the dash cover.. The heater core may also need to be removed for more room. So I am guessing that you will need to remove the dash cover and the AC components to free the harness which may be held down by some more supports under the dash cover.

 

[Branton]

Just going by the pictures it does seem that the ac unit(blower unit) need to be removed to access the harness under the dash cover.. The heater core may also need to be removed for more room. So I am guessing that you will need to remove the dash cover and the AC components to free the harness which may be held down by some more supports under the dash cover.

Thanks for the input! I think that’s what I’m going to have to do. I’m hoping to not need to remove the heater core but we’ll see.

 

[Aaronzdtv]

Thanks for the input! I think that’s what I’m going to have to do. I’m hoping to not need to remove the heater core but we’ll see.

Did you figure everything out? I’m attempting to repair my harness myself since the dealer wants $3000 for the harness alone plus $1500 labor. Am I going to need the dash removed to access the harness thru the firewall?

 

[Aaronzdtv]

Did you figure everything out? I’m attempting to repair my harness myself since the dealer wants $3000 for the harness alone plus $1500 labor. Am I going to need the dash removed to access the harness thru the firewall? If you could go thru the steps you took that would help the Genesis community out for sure!

 

[Branton]

Did you figure everything out? I’m attempting to repair my harness myself since the dealer wants $3000 for the harness alone plus $1500 labor. Am I going to need the dash removed to access the harness thru the firewall?

Yes, the job is done. Car runs great. Was going to make a post in the next couple of weeks. Yes, the dash will need to come out. It’s basically one big loop from the engine bay to the interior connectors. Dash and blower unit will need to be taken out. Feel free to give me a call, I can give u some more info

 

[Aaronzdtv]

Yes, the job is done. Car runs great. Was going to make a post in the next couple of weeks. Yes, the dash will need to come out. It’s basically one big loop from the engine bay to the interior connectors. Dash and blower unit will need to be taken out. Feel free to give me a call, I can give u some more info

Can’t take calls but could you text me 6013076161

 

[Charlie1982]

Wow, this is amazing. For a while, it seemed like companies were basically building their cars around the heater core (i.e., everything else had to be removed before you could get to the heater core). It sounds like these cars are built around the wiring harness instead! Well done, I’m another guy who would like to see your write-up on this job.

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[Aaronzdtv]

Yes, the job is done. Car runs great. Was going to make a post in the next couple of weeks. Yes, the dash will need to come out. It’s basically one big loop from the engine bay to the interior connectors. Dash and blower unit will need to be taken out. Feel free to give me a call, I can give u some more info

Hey do u remember how you removed the engine harness?

 

[Branton]

Hey do u remember how you removed the engine harness?

Yes, will you be having the engine in or out for this part?

 

[Aaronzdtv]

Yes, will you be having the engine in or out for this part?

The engine is still in the car, brand new engine. Im trying to get the new engine harness in as that is last part to install. It looks like everything’s in the engine bay and I wont need to pull anything thru the firewall jus by inspecting your pictures. Correct me if I’m wrong, I don’t want to remove the harness on the inside of vehicle dash jus the one attached to the engine.

 

[Timparton]

Hey do u remember how you removed the engine harness?

Did you wiring harness plug straight back up? Like plug and play

 

[Aaronzdtv]

Did you wiring harness plug straight back up? Like plug and play

As far as I can see yes, jus plug the connectors, bolt down engine grounds, and zip tie the harness safety in the engine bay.

 

[Timparton]

As far as I can see yes, jus plug the connectors, bolt down engine grounds, and zip tie the harness safety in the engine bay.

Thanks I have the 2012 3.8 and would like to RSpec swap it just haven’t been able to find out any info about it