94 Ranger 4.0 engine into a 91 Ranger

[FordRanger1991]

Hey so I have a 94 4.0 Ranger engine that will be going into my 91 Ranger that has a 2.9.
I have the engine harness for the 94 4.0 however should I get the full engine bay harness from a 94 ranger to make things easier on me for the swap? or should I attempt to get a 91 or 92 engine bay harness? I am just trying to make this easiest with the least amount of wire corrections. The local junk yard has an engine bay harness for a 94 but I wanted to see if i should hold out and find a 91 or 92 harness. Also, I want to make sure the 91 and 92 engine bay harness would work with the 94 engine harness.
Hope this all makes sense.
Thanks for the help

 

[FordRanger1991]

So after looking at the engine compartment and wiring harness of a 94 ranger i decided that i will attempt to get a 92 engine bay harness because then i wont have to re-position anything.

94 Ranger 4.0 engine
92 Ranger 4.0 engine harness
92 Ranger 4.0 engine bay harness
92 ECM

So i did some reading on the wire diagrams and it looks like the 92 4.0 engine bay harness only has 1 exhaust o2 sensor
Whereas the 94 4.0 engine bay harness has 2 exhaust 02 sensors.

That's the only real difference I could find. All the other sensors for ignition and emissions and air/fuel seem to be the same exact thing.

Now I just need to figure out my gas lines and then i should be ready for the swap.

So i am assuming i could use all 92 ranger harnesses with 92 ecm on a 94 4.0

You all think this will work well? I just don't have a donor vehicle so i have to find all the random parts. Thanks!

 

[FordRanger1991]

So I don't know if anyone is reading this or not but I am going to just keep up dating the thread so that i might help someone who reads this.

So from the local junk yard i found these things from the same ranger that was a manual and 2wd. This should work fine because I have a manual tranny and a manual transfer-case. I also made sure that the 92 from the junk yard was not set up to pass California emissions because the 4.0 that I have right now is not.

92 engine bay harness
92 engine harness
92 computer

I am currently re-building the engine right now so i can make sure it will last a long time after the swap.

I will post pictures and things I have found out along the way once I actually start installing everything in the truck.

 

[FordRanger1991]

Progress

So I got some things done on this swap and everything is coming together well.
I have pulled the 2.9 from my truck and pulled the engine bay harness and computer.

Here is a pic of the 92 ranger that I jacked the harness and comp from.

The 4.0 Harness...Looks fun

So the gas lines ended up working fine. I will just connect them right up with a gas line disconnect tool

There were some different connectors for what I am assuming to be for the rear lights. But those wires from the 91 to 92 harness are identical in color so that will be an easy fix.
I pretty much have everything figured out except how to figure out which wires do what on the main fire wall plug.
I noticed 8 different wires between the 91 connector and the 92 4.0 connector (those wires have the green tape on them). I simply will re-pin the 92 connector when I figure out how I need to change those 8 wires.
This is the 91 connector that I cut off of the engine bay harness so that I could look through the wires easier.

I have the EVTM book for both the 91 and 92 Ranger so but they only refer to this plug and they don't actually go into detail on it.
Will I simply have to follow those 8 wires to find out what they are and then make the changes accordingly? or is there an easier way? I just don't want to waste time following wires if I don't need too.
Thanks for looking. I hope this all makes sense.

 

[PlumCrazy]

Should be able to just plug the 4.0 bay harness right into the 2.9 dash harness.

-PlumCrazy

 

[FordRanger1991]

Should be able to just plug the 4.0 bay harness right into the 2.9 dash harness.

-PlumCrazy

Ya but I am worried about the 8 different colored wires. Also, the 4.0 harness plug has an extra wire that I need to know if I need.
I am thinking I will just need to follow those few and see where they lead because the EVTM wont help me with them.

Thanks for the response though! The other 150 people that have read this haven't said anything lol

 

[PlumCrazy]

Did your donor have the same options? Cruise, power windows, power locks, push button 4x4 etc.

-PlumCrazy

 

[rummblindohcv8]

Interested to see how this goes. I am swapping a 93' 4.0 into and 89' in place of a 2.9. But I was planning on going the route of swapping all the 93' electrical over. Maybe Ill start looking for 89-93 4.0 Harnesses and ECM.

 

[FordRanger1991]

Did your donor have the same options? Cruise, power windows, power locks, push button 4x4 etc.

-PlumCrazy

well the donor was only 2wd and that was fine for me because my ranger has a manual 4x4 shifter. The other ranger didn't have cruise but I don't believe the cruise even runs through that plug. It runs through the fire wall by itself.
As far as electrical goes, the donor didn't have power windows or locks but mine doesn't either.

The 4.0 harness has a black/white wire in the number 48 pin but the 2.9 doesn't have a wire there.
The 4.0 harness also has a black/Pink wire in the 42 Pin but the 2.9 doesn't have a wire there.
The other couple of differences are just colors

The donor also had AC and mine does not. That could be what that pin 48 or 42 wire deals with I guess.

I think AC and cruise where the only differences between the trucks that wiring would deal with.

It would be awesome if my EVTMs had a diagram with descriptions of those plugs.

Thanks for the comments

 

[FordRanger1991]

Interested to see how this goes. I am swapping a 93' 4.0 into and 89' in place of a 2.9. But I was planning on going the route of swapping all the 93' electrical over. Maybe Ill start looking for 89-93 4.0 Harnesses and ECM.

If your just going with the engine bay Harness (like me) then get one from a 90-92 Ranger because this will make things easiest for you. The way I am doing it with just the engine bay harness seems really simple so far. The only problem I am having is those 8 wires haha But I am sure I will figure them out easily once I can take the time to follow them.

 

[Scott B.]

WHen I put the 5.0L in my '93, I removed the 4.0 engine harness from the chassis harness, then tied the leads from the 5.0 harness into the truck's chassis harness.

Don't mess with any wiring you don't have to - your truck/chassis harness is not changing. Only the engine part is. (And the computer)

 

[FordRanger1991]

WHen I put the 5.0L in my '93, I removed the 4.0 engine harness from the chassis harness, then tied the leads from the 5.0 harness into the truck's chassis harness.

Don't mess with any wiring you don't have to - your truck/chassis harness is not changing. Only the engine part is. (And the computer)

So by changing the total engine bay harness which is the picture of the wire harness from above (I am guessing that is what you mean by "truck/chassis harness") I will eliminate having to rewire the extra/different sensors the 4.0 has that the 2.9 didn't. Now I wont need to run wires for things like the ignition control module and the crank position sensor to the computer. The way I am doing it is only requiring me to figure out the difference between 8 wires on the driver side fire wall plug. So I don't see how changing just the engine harness could make it easier for me. Needless to say the 2.9 engine bay harness is already out so I will be putting the 4.0 engine bay harness back in with the 4.0 comp.

 

[SenorNoob]

Fuel Injectors?

Just wondering what you're doing as far as fuel injectors. I noticed that the parts are different for the 92 engines than the 94. I just bought the same parts. (94 Ranger 4.0 and 92 Explorer ECU). This thread explains better than I ever could. http://www.therangerstation.com/forums/showthread.php?t=89813.

BTW. Does anyone know why the injectors changed? I'm guessing it had something to do with the SEFI but if so then why does the 94 Ranger then not have SEFI but does have the injectors?

 

[FordRanger1991]

Just wondering what you're doing as far as fuel injectors. I noticed that the parts are different for the 92 engines than the 94. I just bought the same parts. (94 Ranger 4.0 and 92 Explorer ECU). This thread explains better than I ever could. http://www.therangerstation.com/forums/showthread.php?t=89813.

BTW. Does anyone know why the injectors changed? I'm guessing it had something to do with the SEFI but if so then why does the 94 Ranger then not have SEFI but does have the injectors?

Hey man thanks for posting this! I totally didn't even think about injectors.
I will probably be going with 92 injectors. I will just go grab some from the local junk yard, clean them, and put new o-rings and filters on them.
I still wonder though how running those 94 injectors with the 92 computer would effect the engine performance.
One of the guys from that link you posted was talking about different MAF sensors but Fords Part # for 90-94 Rangers seem to all have identical ones.
Anyways Thanks for the heads up

 

[FordRanger1991]

Camshaft Synchronizer

So I have finished all the wiring on the truck and I am excited to say that all my lights and electronics work.
But the problem... I ended up having to buy another engine because the 94 (non California) 4.0 that i originally had is junk and would take a bore job to fix. Anyways so I got my hands on another 94 4.0 (California model) that has a Camshaft Synchronizer and all the EGR crap for California. Anyways so I am going to take the intake system from the 94 (non California ) and put it on the 94(California) Block. So as already stated above... I have a 92 (non-California) harness and 92 4.0 comp already installed in the truck. In 92 I don't believe there was a Camshaft Synchronizer in the 4.0s so should I just leave that Synchronizer plugged into the back of the engine and leave it alone? Or will I need to do something with it? Is there a little mechanical device that i can take from the non California engine and put it in the block of the California engine thats going in my truck? I Know something must be there to keep the oil pump turning correct?

I appreciate the time and I just wanted to make sure of this last thing before i throw her back together to get her on the road.