i need help i converted my 1987 t5(manual) car over to a c4 everythign is in and ready to rock this is my first time ....on the c4 tranny there are 4 wires comign otu the side fo it....and i have 2 harnesses comign out the bottom of my car that went to the t5.....all i need is a detailed list or description tellign me how to get the car running and what wires go were or what to disconnect...as what do i do for the neutral safety switch ..just help me please get it started and driveable ....the quickest easiest way...i need my rev lights as well...i dont care fi it starts in everygear or what not for now...
help with c4 swap
- Thread starter 91lxntch
- Start date
78cobra347
New Member
I just did this on my 89 coupe was not hard.
The 4 wires on the tranny are 2 for for neutral safty switch and the other 2 are for reverse lights as for colours i cant remeber but u can figure them out with a ohm meter
When in park and neutral 2 will be closed loop and the other 2 will be in close loop in reverse position only.
Now 1 of the plugs hanging down from the floor will used the other will not be used.
Look for the plug that has a red wire looped back in to the plug that is the start wire u cut and join them to the 2 wires at the neutral safty switch and the other wires go to a plug that is a push on connector on the T5 that is the reverse light wires, cut the plug off and join them to the other 2 wires of the tranny.
Under the dash u will have to bypass the clutch safty switch at the top of the clutch pedal.
Hope this helps, please dont make me jack up my car and take pics lol good luck it is not hard.
The 4 wires on the tranny are 2 for for neutral safty switch and the other 2 are for reverse lights as for colours i cant remeber but u can figure them out with a ohm meter
When in park and neutral 2 will be closed loop and the other 2 will be in close loop in reverse position only.
Now 1 of the plugs hanging down from the floor will used the other will not be used.
Look for the plug that has a red wire looped back in to the plug that is the start wire u cut and join them to the 2 wires at the neutral safty switch and the other wires go to a plug that is a push on connector on the T5 that is the reverse light wires, cut the plug off and join them to the other 2 wires of the tranny.
Under the dash u will have to bypass the clutch safty switch at the top of the clutch pedal.
Hope this helps, please dont make me jack up my car and take pics lol good luck it is not hard.
If using an aftermarket shifter, you can get rid of the stock wiring on the tranny and use the two micro switches that come with the shifter.
ok as far as under the dash is concerned i can push my clutch pedal in and cover with the factory carpet you cant tell it is there is that good enough to complete the circuit for that part or will i need to cut and splice those 3 wires together as well..
p.s thanks for the info....yes this job was easy except for i have long tube headers what a pain..the only part was the wiring thanks
p.s thanks for the info....yes this job was easy except for i have long tube headers what a pain..the only part was the wiring thanks
ok here is what i got so far...there are 4 wires coming from the c4 2 red w/ blue stripe(these are for nss) and 2 others ..i got 2 harness's coming from the floor that went to my t5 ..1 has only 2 wires and i believe im not going to use this.. the other has 4 wires 2 of them go to the other 2 on the tranny which work my rev lights i got them working so that leaves the 2 red on the tranny and the 1 red and 1 whitish yellow on the floor i connected only the one red wire from the floor to the 2 red wires on the tranny and got nothing..i also unplugged the 3 red wire harness from the clutch pedal and used a fuse to jump them still nothing...in all this i did never use the last wire from the floor harness i cut off..can you explain a little better for me what am i doing wrong
p.s im making progress i got the rev lights figured out
p.s im making progress i got the rev lights figured out
To make it legal track wise and restore factory operation, extend the clutch start switch to the tranny neutral start. Two wires, doesnt matter the order, it is just an open or close.
You can remove the clutch pedal and just have the 2 pedals. My car was a 5 speed factory car and is now an auto.
My wiring is all hand done, so I cant translate colors, etc.
If you have the reverse lights, the neutral safety is a snap.
You can remove the clutch pedal and just have the 2 pedals. My car was a 5 speed factory car and is now an auto.
My wiring is all hand done, so I cant translate colors, etc.
If you have the reverse lights, the neutral safety is a snap.
i dont care about being legal at the track at this point i just need encouragement from getting it started easiest way possible....there is 3 wires not 2 on my clutch pedal....i will eventually get an aftermarket shifter and get it all legal ...but can soemone help me on this subject this makes about 90 hours on this i need to get it done.....all i got left is the 2 wires unused in the 4 wire harness comign from floor...
Does it start and rev lights work at this point? If so, just push in the clutch to start the car. Check to make sure it is in neutral or park when you do so. Tape off the other wires and move on.
I think the T-5 did have a neutral sensor for the cruise control. The clutch pedal 3rd wire is likely for the same thing.
I think the T-5 did have a neutral sensor for the cruise control. The clutch pedal 3rd wire is likely for the same thing.
ok maybe im confusing you....so here is what i did so far,
i unplugged the harness from my clutch pedal and jumpered it..which i was told this wil bypass having to have the clutch in....i also found the 2 wires that work my rev lights and wired them together ...the car will not start i have 2 red w/ blue stripe wires on the tranny and 1 red w/ blue stripe wire and 1 whitish/yellow wire comign from the floor do i connect all 4 together...all i have left to do is get ti started then il go back through another day and do it the proper way with the correct pedals for an auto i just need to get ti running to gain back some confidence it took me a few hours to do the swap but its been 2 days on the freakin wiring...if someone would jack there car up and tell me what color wire goes were on the tranny that would prob do it for me......thanks for all your help though..im afraid to just start touching wires together ....
i unplugged the harness from my clutch pedal and jumpered it..which i was told this wil bypass having to have the clutch in....i also found the 2 wires that work my rev lights and wired them together ...the car will not start i have 2 red w/ blue stripe wires on the tranny and 1 red w/ blue stripe wire and 1 whitish/yellow wire comign from the floor do i connect all 4 together...all i have left to do is get ti started then il go back through another day and do it the proper way with the correct pedals for an auto i just need to get ti running to gain back some confidence it took me a few hours to do the swap but its been 2 days on the freakin wiring...if someone would jack there car up and tell me what color wire goes were on the tranny that would prob do it for me......thanks for all your help though..im afraid to just start touching wires together ....
78cobra347
New Member
Did u find the red wire that loops back into the the plug under the car?That is the wire u have to cut and connect to the tranny park switch.
It should start before u cut it in any gear.
It should start before u cut it in any gear.
MrKwik
Founding Member
On my 93 vert that I swapped a 5.0/C4 into, the neutral safety wires are blue with a red stripe and white with a red stripe on the car end and on the tranny end they are both blue with a red stripe. I used a weatherpack terminal to hook everything together but if you just want to fire it, you can just twist the two on the car end together to bypass the safety feature and it will start.91lxntch said:
no the car dosent haver cruise control i got the harness under dash correct...
i am not seeing any red wire that loops back in....here is what i got
1 connector with 2 wires(i dont belive i use it ,in fact i dint think i used it on my t5)
1 connector with 4 wires , 1 red,1 whitish,2 black( this is the connector i got my 2 rev wires from and they work, they were the 2 black wires....so what your saying is to wire the one red from the floor harness to the 2 red on the tranny?? im sorry guys im just so confused here....i dont see anythign looping back in
i am not seeing any red wire that loops back in....here is what i got
1 connector with 2 wires(i dont belive i use it ,in fact i dint think i used it on my t5)
1 connector with 4 wires , 1 red,1 whitish,2 black( this is the connector i got my 2 rev wires from and they work, they were the 2 black wires....so what your saying is to wire the one red from the floor harness to the 2 red on the tranny?? im sorry guys im just so confused here....i dont see anythign looping back in
MrKwik
Founding Member
Now you got me confused. I was thinking that the wire in the floor harness was blue with a red stripe not red with a blue stripe. Either way...there is one wire in the floor harness that is the same color as the 2 wires in the transmission weather its blue/red or red/blue. Hook it to one of the transmission wires. Hook the other red/blue (or blue/red) wire on the transmission to the white wire with a red stripe in the floor harness. Basically you just need to hook the two remaining trans wires to the 2 remaining wires in the floor harness, doesnt really matter which you hook to which because its not like hot and ground, it just completes the circuit.91lxntch said:
MrKwik
Founding Member
OK...I crawled back under my car and looked at the wires again. They are definately blue with a red stripe on the tranny side and on the floor side. one is blue with a red stripe and the other is white with a red stripe.
MrKwik
Founding Member
Shouldnt matter. I recently went through starter issues with my C4 swap. The bellhousing and the seperator plate are what locate the starter but the starters are all the same reguardless of transmission. You do have the seperator plate in there don't you?91lxntch said:
The manual and auto starters have a different snout. In my previous experience of manual to auto conversion (truck), the starter snout will rub on the flywheel if the manual starter is used in the auto tranny. Never tried the opposite.
MrKwik
Founding Member
The starter on my C4 is out of an 85GT 5-speed and it works fine. Before I realized I had the wrong bellhousing (long story) I tried several starters from the parts store and found that for the most part there were only 2 different part numbers for about 6 different applications that I tried from 78 to 93, auto or manual didnt matter. And either would work, the difference is that the later mustang starter is geared lower so that it cranks easier. It is also about half the weight of the earlier one and alot easier to install since its so much smaller. Its also about $30 more.hllon4whls said:
