I just put an 87 2.8 into my 85. I am almost done. I noticed a connector hanging down by the muffler and pulled it up. It is a 6 pin. red power wire on one end with yellow beside it. do not recall the other colors. Wondering where it goes. If a pic is needed I will try to post one. thanks.
Yes... otherwise none of those systems will work. To begin with, the back up switch on your car is attached to the shifter mechanism under the center console, and the park/neutral switch on your car is on the clutch pedal. If you have both wiring schematics and you know your way around wiring, then it's not too hard to make it work, but it's not very easy to explain all the things you need to do, if you don't. There are going to be several pin out changes as well to the large connector (C500) that connects to the chassis near the battery.
You are going to have to cut the large Purple and large Yellow wires off of the connector. Then splice together the large Purple to the large Yellow (Starter Wire). Then at C500, you need to pull the white secondary pin retention clip from the side of the engine harness connector. Once removed you need to bend the tang down on the large Yellow wire. Once bent down the yellow wire will pull out of A-4 the connector from the back. Bend up the tang back to it's original position. Then re-install the yellow wire into position E2. Re-install the white clip
Note - if you don't find and remove the white clip the pin will not come out no matter how hard you pull.
---- The other four/five wires on the connector won't be used If you wish you can leave the connector on and tywrap the connector to the harness. The blue 4 pin transmission connector also will not be used. ---- The Purple/Yellow wire runs to the VSS connector. On the automatic that is located under the alternator. On your 4 speed the VSS is near the flywheel. You will have to extend the wires to reach the new location of the VSS.
---- What alternator did you use?
---- No change needs to be done to either the clutch switch under the dash or the reverse switch in the console. Leave them alone since you are going to want to keep them working exactly how they were working before.
Last thing - Your 87 2.5 Prom is programmed for an automatic transmission. It is recommended that you use a 87-88 2.5 MT PROM. If possible perhaps you can get one locally. If needed I can supply one for $40 + shipping.
[This message has been edited by phonedawgz (edited 03-23-2014).]
thanks for all the info. I appreciate it. I have been a bit confused. What I really have is an 87 set up in an 85 car. Everything is identical to my 85 down to the four speed. I guess it had been an automatic at one time because that six pin connector was there. I took a closer look and it looks like the two wires have already been shorted together on the connector. It was running fine in the 87 when I got it. I will check closer tomorrow at all the wiring. I guess this is the least of my worries right now. My best friend is a mechanic and he and I had an argument so I may have to stumble through the rest of this by myself. He had the back calipers on but not connected, I have to finish that. I stupidly waited until the engine was in before deciding on a new water pump and then broke a bolt. Got the pump off and bolt will not budge. Guess I will try heating it. Too many directions I am going. lol I can do wiring so I will check that first. I forgot to mention it is the 2.8 I am working with. again thanks. Don't know what I would do without the great people on here freely giving their knowledge to us non mechanics.
Big thank you for the information. It is exactly what I needed to do. Started right up after I moved the pin on the c500. I am gonna bleed all the air out of the systems today and see If I can still drive it after 6 months of it sitting around. again thanks. scott.
My 85 four speed will start in gear. Not really any issue (my wife doesn't drive it LOL) but I did notice a white plastic pin switch that is hanging by the clutch, not in place. I guess that's the clutch switch. Tomorrow I will squeeze it together and if the engine won't start, that verifies it is the clutch switch. I may hook it back up if the mount for it isn't broken.
------------------ ===Always trying to find time to work on cars=== Louis Duet Baldwin, Long Island, NY Where driving hard is SOP. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ "Blue" <= '85 Fiero GT Stock V6---Stock everything. Trying to keep it 'mostly' that way. ~~~~~~~~~~~~~~~~~~~~~ "Boo" <= '81 Delorean DMC-12 The "DuetLorean" VIN #5835 Stock PRV engine Robertson Equipped Neiland/Delman Engineered Carbed and loving it! (Peugot 604 manifold) ---"Sorry purists"