question about manual vs auto harness

[BigKO]

Hey guys, I just recently picked up a car that is a 5spd. turbo. Motor and transmission are out of the car, and im getting ready to put in a motor that has been hooked up to an auto its whole life.
I have all manual transmission parts (came on the car i bought) but I was wondering if the auto harness i have on the motor I'm putting in would hook right up to the manual ecu and plug into the manual tranny without issues. can anyone confirm or refute this? it would be a lot easier than swapping the two harnesses as well.
Ive heard of people having to bypass the neutral safety switch before but i am not sure if i will have to do that in my particular case because i will not have to mess with clutch pedals etc. just worried about whether or not the the two harnesses are interchangeable. All help is appreciated, and sorry for the long post. But details are needed in order to help solve problems :naughty:

 

[Another MkIII]

Hey guys, I just recently picked up a car that is a 5spd. turbo. Motor and transmission are out of the car, and im getting ready to put in a motor that has been hooked up to an auto its whole life.
I have all manual transmission parts (came on the car i bought) but I was wondering if the auto harness i have on the motor I'm putting in would hook right up to the manual ecu and plug into the manual tranny without issues. can anyone confirm or refute this? it would be a lot easier than swapping the two harnesses as well.
Ive heard of people having to bypass the neutral safety switch before but i am not sure if i will have to do that in my particular case because i will not have to mess with clutch pedals etc. just worried about whether or not the the two harnesses are interchangeable. All help is appreciated, and sorry for the long post. But details are needed in order to help solve problems :naughty:

If you have a manual harness, useing it will be easier. Is the harness still in the car, or did you pull it with the motor? Did you pull the trans and motor together or leave the trans in?
-AM3

 

[RazoE]

Its fine. Hell you can even keep your auto ECU....

 

[BigKO]

Its fine. Hell you can even keep your auto ECU....

oh ok, Yeah the manual ecu is in the car right now, and i was planning on pulling the auto motor with harness and putting it into the other car (and hoping it would just hook right up with no issues). SO i wont have any problems with the neutral switch on the clutch or a loss of cruise control? because I have read of people having to bypass that or wire it in a certain way on here.

 

[BigKO]

If you have a manual harness, useing it will be easier. Is the harness still in the car, or did you pull it with the motor? Did you pull the trans and motor together or leave the trans in?
-AM3

i pulled the motor and trans together, and then took the 5spd off of the motor, so that i could put it on my good one. the manual harness is on the old (rod knocked) motor, and seems to be perfectly in tact. However i was hoping to just take my auto motor out with harness and hook it up to the manual transmission and put it back into the original 5sp car. (the one with manual ecu, drive shaft, etc) hope that wasn't too confusing.

 

[BigKO]

so just to confirm everything should bolt and plug right up? or not? because you two seem to be at a contradiciton

 

[Another MkIII]

so just to confirm everything should bolt and plug right up? or not? because you two seem to be at a contradiciton

I've was under the impression that some things are different (Neutral safety, etc.) Let me double check.
-AM3

 

[BigKO]

I've was under the impression that some things are different (Neutral safety, etc.) Let me double check.
-AM3

ok thanks

 

[Another MkIII]

ok thanks

Which manual trans do you have?
What year is your car, and what year did your new motor come out of?
-AM3

 

[RazoE]

I have an auto harness on my w58-7MGE to 7MGTE swap and kept the w58, so it is doable. But if you want everything to be plug and play, then swap out the harnesses, however if it's from a different year, some plugs will not mat up, but can be re-pinned...

 

[BigKO]

I have an auto harness on my w58-7MGE to 7MGTE swap and kept the w58, so it is doable. But if you want everything to be plug and play, then swap out the harnesses, however if it's from a different year, some plugs will not mat up, but can be re-pinned...

both cars are 91 both harnesses are 91 and both cars are turbo so the trans is an R154. But to make it plug and play I should swap the harness? I see no problems with different plugs because both of them are the same year

 

[Another MkIII]

both cars are 91 both harnesses are 91 and both cars are turbo so the trans is an R154. But to make it plug and play I should swap the harness? I see no problems with different plugs because both of them are the same year

Does the auto harness have a plug for the rear speed sensor on the R154? The only plugs you need for the R154 is the back up lamp plug, and the rear speed sensor.
-AM3

 

[ForcedTorque]

I have always been told that the auto parts will work for a 5-speed. But, you particular question has me puzzled. The question about speed sensor plug is a good one. If you have that, I'd say it will work.

If you can't get a satisfying answer to your question, it is very easy to swap a harness while you have the motors out of the car. You really don't need to mark anything except maybe the injector plugs. Everything else uses a different type plug, so you can't plug things in wrong.

 

[BigKO]

yeah like you say, ill have to look and see what plugs the auto harness has. If it has the two correct ones, i may just try and use it. But in order to save myself time i may just give the manual harness a good lookover for any damages and use that one, because like you said swapping harnesses should be tooo bad i'm hoping.
Better to be safe and have the exact correct wiring then mess around with the auto one once i get it in the car. Was hoping I could save myself that time though.