I want the most simple 4.0 possible.

[Burnside]

I am currently in the middle of putting a 4.0 into my 1989 bronco II that had a 2.9 liter in it. The 2.9 is already out and I'm freshening up the 4.0 before it goes in. A while ago I did the a4ld to m5od swap so that's all already in there... From what I've read there's nothing really to putting the 4.0 in there other than just dropping it in and bolting it to the cross member. right? same engine mounts same holes in the cross member as the 2.9; 4.0 is essentially a bored and stroked 2.9 right? but what this post is about is I want to know how simple can I do the wiring. What is essential? I could make my own wiring harness for the most part. This is for a wheeling rig so I don't care about the gaugs in the dash working, or if the dome light kicks on when the door is open. I know this is gonna take me a lot of digging through wiring schematics but I was wondering if anyone know what sensors etc where necessary to get a 1991 4.0 to run? any suggestions would be appreciated. or If i'd just be better off using the oem harness. it just seems from what I'm asking out of the truck there's about a couple hundered too many wires.

 

[AllanD]

Start at the passenger side kick panel and remove the engine computer.

PUSH the gromet for the fat cable that goes to the computer through the firewall along with the connector.

Run that wiring as far as you can disconnecting it from everything.

REPLACE it with the same fat harness from a 4.0 '90-92 Ranger
Plug it in.

That pretty much deals with the job of wiring.

There are a FEW small issues, but those are easily dealt with.

It bugs the hell out of me to hear Gen2 guys complain about
the "difficulty" of an engine swap because they have no idea
how EASY they have it.

And like you they seem to get wrapped up in the differences instead of
"going with the flow" and letting the similarities guide them.

I put a '93 Explorer engine and wiring into an '87, by comparison your swap is EASY.

And I suspect that if you have "a couple hundred too many wires" that you have an EXPLORER harness, which is wired differently and many of those wires have to deal with the rear window defogger, power windows and doorlocks, etc...

If you don't have the EVTM for BOTH your '89 AND the vehicle that provided the donor harness then it can EASILY seem like a hopeless task, but that is entirely up to you
to deal with.

Might I suggest that you search ebay for an EVTM?

Here I took 90 seconds and did it for you...

ebay items:
220124075383 1991 Ranger EVTM, (not necissarily this one in particular I saw
atleast three in the buy-it-now listings)

220149255235 1989 Ranger/Bronco2 EVTM (there are five of these on ebay)

330167506439 1992 Explorer EVTM, it's $24.95 B-i-N, but it's the only one on ebay at the moment....

The 1992 wiring isn't different in the engine management wiring so if you cannot find a 1991 explorer EVTM a 1992 will work just as well, but you need one of the two, a 1993 EVTM would be utterly useless to you.

If you don't have these service publications go to your local hardware
store and buy a length of rope.... to end it all and save yourself the aggrevation....
Oops, that's right you have a big waring harness that'll serve that purpose and save you the trip to home depot for rope...


Yes, the 4.0 bolts in and even bolts up to your current 2.9 Y-pipe

You'll also need the air cleaner box (to mount the Mass air meter)
but it mounts to the same plastic bracket on the passenger side inner fender

I suspect all the "complication" you are looking at is because you have
an explorer harness, right?

AD

 

[rickcdewitt]

damn!

son of a b*@ch! allen are you saying all i needed to swap my 91 2.9l to a 4.0 is the computer and engine bay harness from a 90-92 ranger!do you need to re-pin any connectors on the dash side?i must be an idiot,the wiring is what kept me from putting my 91 explorer m5od and 4.0l with 50,000 on it in my truck.

 

[CopyKat]

Red/green is accessory/run
Red/blue (14 ga Pink) is Start signal.
Black/white is sensor ground


From chassis side.
Black/pink is Fuel pump power.
Black is ground

With these 5 wires it should start. Everything else is guages.

 

[CopyKat]

allen are you saying all i needed to swap my 91 2.9l to a 4.0 is the computer and engine bay harness from a 90-92 ranger!

Yes

It will be a plug and play if you use a Ranger harness from the same year. This also goes for swaps into B2's.

Between 90 B2 and 91 Ranger there are a few pins different. They just need to be re-pinned. They also changed plugs around (Male/Female).

Explorer harnesses are pinned different. Going throught the firewall plug.

A 91 sploder harness is not a plug and play in a 91 ranger.

 

[rickcdewitt]

thanks for the reply man,no offence ment in your meh thead. it makes sense that ford woulden't change the harness much from a 91 2.9 to a 91 4.0.awsome now i just need to get a vehicle(or person) i can unload all my worthless 2.9l performance stuff on.do you guys know if the 2.9 headers will work if a bung is welded on for the recirculation?

 

[CopyKat]

do you guys know if the 2.9 headers will work if a bung is welded on for the recirculation?

No.

The header flange is different.

If you could get someone to recut a flange you may be able to get the 2.9L headers to work, with a tad bit of tube work.

 

[rickcdewitt]

No.

The header flange is different.

If you could get someone to recut a flange you may be able to get the 2.9L headers to work, with a tad bit of tube work.

i have access to a plasma cutter,and the tubes and collectors on the jba's are pretty big.hell this is sounding more realistic all the time.i wonder if i could use the explorer smog stuff or would need to also take the ranger smog.here in california it would probably just be easiest to swap on a 4.0 cab(for a ranger like mine thats getting a bobbed bed and new front clip anyway)and let the smog tech think its a factory 4.0 so it doesn't need to go through the smog referee bull.

 

[CopyKat]

i have access to a plasma cutter,and the tubes and collectors on the jba's are pretty big.hell this is sounding more realistic all the time.i wonder if i could use the explorer smog stuff or would need to also take the ranger smog.here in california it would probably just be easiest to swap on a 4.0 cab(for a ranger like mine thats getting a bobbed bed and new front clip anyway)and let the smog tech think its a factory 4.0 so it doesn't need to go through the smog referee bull.

What year smog equipment? If it's 93 going into a 91 you should be better off. It would have to pass smog for the 91 ranger year. If it comes out cleaner then your laughing.

 

[rickcdewitt]

What year smog equipment? If it's 93 going into a 91 you should be better off. It would have to pass smog for the 91 ranger year. If it comes out cleaner then your laughing.

you'd think that they would just accept a cleaner emission as proof but down here to be legal you need all the smog from the donor motor and it needs to be the same year or newer motor.i guess if the smog was the same type the referee woulden't be able to tell(or at least might not care).then you take it to a referee who confirms the smog install and you get a tag or sticker so its legal to smog.big PIA process compared to sneaking a 4.0 cab on my truck and registering it that way.all this is only if you intend to sell it later not just use it up,in which case i could get away with anything in this county.

 

[AllanD]

son of a b*@ch! allen are you saying all i needed to swap my 91 2.9l to a 4.0 is the computer and engine bay harness from a 90-92 ranger!do you need to re-pin any connectors on the dash side?i must be an idiot,the wiring is what kept me from putting my 91 explorer m5od and 4.0l with 50,000 on it in my truck.

That is damn near the case.

The thing with the "complete" Explorer harness is that there is stuff that is wired (routing) or in some cases fused differently than on the ranger

One particularly annoying trouble spot for a 4.0 swap on an '89-90 with an explorer harness is making the heater blower work correctly.

On the Explorers the power feed to the blower is done in
the engine bay (with a relay) instead of running the power
through the dash

I heard horror stories about making the tach work on a truck with an implanted 4.0... funny but my original 1987 type tach works perfectly
I even checked the calibration with an external tach...

I put a 1993 Explorer harness into my 87 ranger, but I essentially lopped off
the big connector and connected everything to the seperate plugs that the '86-88's use (in some cases I was able to move the "big plug" pins
into the small plugs)

But then again I spent a solid week leaning over the front of
the drivers side fender connecting and SEALING everything.

But if you open the hood of my 1987 you'd think you were looking at a 1993 explorer, right down to the washer fluid bottle and the cruise control servo.

Most people don't want to go to the lengths I did, nor could they if they wanted to.... it's just WAY too time consuming.

AD

 

[rickcdewitt]

do you need a smog referee to certify it in wyoming allen?sounds like it would pass here in CA with all the emissions.

 

[Burnside]

Thanks for the reply alland, and kopycat that was about what I was wanting to hear. If its a ton easier I'll prolly stick with the explorer's harness but I'm trying to eliminate as many wires as possible and avoid caring about gauges or even blower motors. I just want the engine to run. I'll be surprised if I even have a windshield to defrost for much longer; I'm not worried about it, this is a trail pig. I do wish this was a cleaner going swap, but as circumstances fell I had about half an hour in the dead of winter in the driveway to pull the 4.0. I think I pulled off everything I need but I definately did not have the time to compare the two engine bays label everything etc. etc. and this was almost three years ago I pulled the engine and the 2.9 just crapped out on me so its a good time for the 4.0. I know I have the explorer's ecm and engine wiring harness so I will dig it out and lay it out and look it over but I was looking for more of an answer like kopy cat's. if its that easy though just to stick with the explorer's harness i will. thanks.

 

[AllanD]

Well I recommend you start by removing the 2.9 EEC harness from the passenger side and instaling the explorer harness there first, just get the computer and 60pin connector and the firewall gromet mounted, then work your way "around & Across"

Then take the power distribution box and start systematically removing wires that connect to the ABS system (I presume you aren't attempting to retrofit ABS onto the recipient?)

the Explorer harness has one branch that runs across the firewall,
you can "hang" that on it's screw mount brackets and there are a
couple of connectors that hook to the "on engine" harness.
and of course the lead that runs up to the EDIS module.
(which is mounted to the radiator support forward of the battery)

DO NOT get wrapped up in the scope of the job, concentrate on one
thing at a time, it if proves difficult move onto something else and
come back to it later, NOT thinking about something is often the
best way to work through it.

AllanD

 

[Burnside]

thanks man, sounds like you've done a couple of these before. I haven't even got the 4.0 in the truck as of yet so that's what i'm working on now. The 2.9 is out and I've just been buying things like new engine mounts, pilot bearing, plugs, wires, oil, filters, etc. removed the engine fan because it'll be going in with a taurus electric fan. one thing I might get caught up on is finding my old centering tool to install the flex plate know any tricks to help line it up by hand? I have no extra transmissions to steal the input from and other than buying another clutch kit auto parts stores are saying the alignment tool is obsolete to buy alone. i'll figure it out.