So yeah, good times, with the engine swap.

[Setheroo]

I am nearing that finish line right? Where I have everything in, and the old engine is on the ground, and the new engine..... in the car. Then I was looking at the wiring harnesses, and I just thought to myself... yay! I put a newer engine, that came from a manual, into a older model car, that has an automatic..... I AM MISSING CONNECTORS! Oh and I also have connecters, that I didn't have before!

So now that I have realized my problem... I gotta figure out if switching the harnesses can actually fix my problem....

I have searched for this sorta thing, and I just couldn't find squat, everyone wants their cars to have a manual - so there are tons of guides on how to get your manual going from an automatic... but nothing on getting the automatic going from a manual!

So here is what I have... an 88 auto trans... with old 88 auto engine harness plus ecu

Then I have an 89+ engine thats all built up - ready to go! new pistons, and upped compression, MHG, header... and I got all that jazz in there... with that friggin manual trans harness all wired up....... OOOPS!

Can it even be done.... will the electronics work... or am I doomed to buy some more stuff?!

Thanks in advance.

 

[bluedragon17]

well i know that 89 was the transition year for these cars and alot of tother cars. the 86.5-88 cars use yellow connectors while the 89 use i think grey and the 90-92 use some other color that i dont know. basically if you have an 86.5-88 you have to use that same wiring harness or your looking at alot of custom work also you can use the 89+ harness but you would have to use that ECU and basically re-wire the entire car to my knowledge. my advice would be go the the eccs and electrical topis and ask jet jock he would know better than anyone i can think of besides maybe duane and a mod on here............... just my .02 and advice

 

[conundrum07]

If the harness that is on the engine is for a manual you will have to switch it to an auto harness. The MT harness does not have the necessary wiring/plugs for the auto tranny. Also, be sure that the harness matches your body, since you are an 88 you are going to want a 87-88 harness. Yellow plugs IIRC.

 

[jdub]

Ok...I'm a little confused (of course that's easily done)

Correct me if I'm wrong...you have in the car now:
- '88 harness, ECU, ETC and Auto Tranny

You want to install:
- '89 motor w/ sensors and an '89 manual harness

Is this correct...be specific.

 

[supramacist]

he had a manual...., stock. then he swapped to an automatic. seemingly, he is looking for the 411 on how to complete his build.

So ya, he needs to take a deep breath eaze up on the ridalin, lol. Let's just take it from the top.

ACTION!!!!!!

 

[Setheroo]

Ok...I'm a little confused (of course that's easily done)

Correct me if I'm wrong...you have in the car now:
- '88 harness, ECU, ETC and Auto Tranny

You want to install:
- '89 motor w/ sensors and an '89 manual harness

Is this correct...be specific.

You have it a little bit backwards, and its ok that you got things turned around.

I have in the car now... the newer engine - that came from a manual... and its all built up... inside of my 88 with an original automatic trans.

I left the manual wiring harness on it... because I never realized that it needed to be switched.

I still have the old wiring harness off of the older engine, and I still have the original ECU - so I don't have a problem at all there. I just believe I have to switch them around.

But the things that I want to know are this...
How hard is it to swap a harness.. I haven't exactly done it before... I am just familliar with plugging and unplugging wires where I knew that they went! lol. There are a few wires that I know exactly what they are to - but not everything.

Ok and now the smalk technical stuff that I am more concerned about. The old ECU... how compatible is it running the newer engine... they didn't change anything too drastic did they? I won't get any dreaded check engine lights that won't go away due to the fact that I have mixed up components (89 engine, on a 88 trans, with 88 ECU).

Well... I really hope that I made it more clear this time around, thank you for everything so far.

 

[jdub]

Ok...now I understand

You will have to swap the '88 harness back into the car...and the '88 ECU. Sorry, but the manual harness is not compatible with an auto tranny (as you figured out). You may have to swap some of the sensors from your old motor to the new one, depending if the connectors plug in or not. The motor will run fine with the correct harness and sensors.

I won't lie to you...this is going to be a pain with the engine in the car. You will likely have to remove the intake manifold to do it. I would follow the harness that's in there and go connector by connector with the '88 harness. Before you put the '88 harness in, I'd go over it and replace the outside sheath where it's cracked, etc. Inspect the wires you can see and repair while it's out of the car.

 

[Setheroo]

I can feel the pain in my ass start to tingle as I think about removing my intake manifold... but that is probably going to be the only way that I can reach the injector wires... plus the wiring seems to run through the middle of the manifold.

This is going to be a blast.

I shoulda went.... 1JZ

 

[Big Wang Bandit]

Just take the engine out. The 1JZ is even more cramped in the car, but its easier to change spark plugs, Thats the only reason I went 1JZ

 

[jdub]

Depends on how high you're willing to let the frustration level go

Pulling the motor will make changing the harness a piece 'o cake...it's just a lot of work. Doing it in the car is going to require yoga moves with your hands...especially if you have to swap some sensors.

 

[Setheroo]

I know that I haven't touched this thread in a while, but I am still working on this problem (haven't had time to work on it much... time has been really hard to find). But after a while of working on the car here and there, here is what I have ran into.

• Distributor wiring, different.. Do I need to put the old distributor on the new engine, or is there a way around that?

• Thermostat/waterneck plugs, seems like I am missing something for it with the old harness - I left the new stuff on the engine... so I assume that I must swap that as well?

• Injector connectors, yeah, those don't plug in - switch the connectors, or switch the injectors?

I definetely can't just put back on the manual harness... so I am stuck improvising everything... and there seems to be so much to switch, any input is greatly appreciated.

 

[cuel]

Usually on jobs like this(OH, how I love them, not), I switch over all the parts and harness from the old motor. Parts being injectors, sensors, intakes, what ever is different. I would have the old injectors cleaned and flow tested since they've been sitting up for a while. Usually the local NAPA can do them, or send them out for you.

 

[Setheroo]

Alright, wiring diagram time maybe? I am going to attempt to use the newer style distributor... truth is I don't have much of a choice, my old one turned up missing.

Here is what I ask - Does anyone have both the wiring diagrams for the ignition for the 89+ NA and the 88 NA?

(I looked on cygnus already, and I couldn't find a way to change the year of the manual, and I am pretty sure its the diagrams from the 89+)

The wiring has got to be different somehow - but it runs off the same principles, so.... there has to be a way to make it work.

The trick is to find out what wires lead into the newer distributor from the new harness... and find those same wires from the old harness, and splice the newer plug into it.

If this doesn't end up working... I am going to be... one unhappy broke college student. But - I know there has to be a way, and knowing that - I keep hopeful.

Thanks in advance.

 

[CRE]

The only thing that changed is the pin order on the distributor plug. The color code is the same.

EDIT: By the way, the TEWD and TSRM on Cygnus are for 89+

 

[Nomad707]

out of curiosity... why did you switch from 5spd to automatic?

 

[Setheroo]

out of curiosity... why did you switch from 5spd to automatic?

I wish that it would have been a choice. I didn't have much money to even buy the engine and all the goodies with that... and well.. the 5 speed would have added even more to the cost.

I do have updates though, I worked on my car a lot tonight. In fact, I got so far that I finally got to turn the key. Too bad that when I turned it, all it responded with was a CLICK. The starter has gone bad.

I already checked to see if it was getting power and a good ground - which it is. Which leaves me with having to replace it.

Anyone know how much a new one might cost - and are the ones you can get at any parts store any good in comparison to buying it from a dealer?

That and is there any known tricks to getting the top bell housing bolt? :evil2: That bolt gave me the worst trouble coming out, and the only way I could even get it out was to lower everything down... now that isn't an option. So if anyone has done it before with everything pretty much in... some advice would be much appreciated.

 

[AJ'S 88NA]

A really long extension with a swivel on the end. That's what I used to do a clutch. Be careful though it has a tendency to slip off the bolt and you may booger up the bolt or your knuckels.

 

[Sl1dewaysSupra]

I have a quick qustion, my car is a 87 manual and the motor that will be dropped in will be from an 87 auto. Will I be seeing some of the same issues you are?

 

[Setheroo]

I have a quick qustion, my car is a 87 manual and the motor that will be dropped in will be from an 87 auto. Will I be seeing some of the same issues you are?

Which harness are you planning to use? You are going to run into some issues, but not many. That is all that I can tell you right now with the information you provided.

Things will be simple because the years are the same. But the computers that control the engine are different, I can tell you that one right off the bat.

 

[johnathan1]

IIRC, you can use an auto ECU on a manual car, but not the other way around.