1989 Ford Ranger (manual trans M5OD) 2.9l engine swap to 4.0 from 94 Ford Explorer (auto trans)

[Rjack90]

Hoping to get some help here I've read through many forums and seem to be getting mixed advice. I have a 89 Ford Ranger 4x4 manual trans with 2.9L motor. I have low compression in two cylinders and she was always gutless regardless. I wanted to throw in a 4.0 L OHV and read how easy it was and all "plug and play". I ordered a reman 4.0 long block from Jegs and picked up a 94 Ford Explorer 4x4 Auto trans 4.0 OHV for a donor. I gutted both the 89 and 94 for the swap (wiring harness and ECU, PCM) and I am in the process of laying out the donor harness in the engine bay. I would like to keep my 89 dash and manual trans. My questions are below.

The Firewall connector from the 94 plugs into the 89 Ranger, but will it work? I have read it will not work with out repinning the connector. Is it worth a try or will it short something and cause more issues if I hook up the battery and see what works? (I have a EVTM on order if this is the route I go)

The donor explorer was loaded with extras, power seats , power windows etc. Lots of extra wires and plugs I wont be using in the 89. Will this cause issues with those not plugged in?

Am I going to have issues with the computer from the explorer being from a automatic and going into a manual? Are the computers actually specific to trans?

I have multiple junkyards close by, would a 90-91 4.0 engine bay wire harness work plug and play into the 89 dash?
Do I need to find a computer for a 4.0 ranger out of a manual?

Any advice would be much appreciated. Thanks.

 

[Brain75]

The donor explorer was loaded with extras, power seats , power windows etc. Lots of extra wires and plugs I wont be using in the 89. Will this cause issues with those not plugged in?
I'd carefully seal off the connectors (so they don't corrode) and keep em in case I decided to add power windows later
Am I going to have issues with the computer from the explorer being from a automatic and going into a manual? Are the computers actually specific to trans?
"I think" yes you will have issues with the computer - it will try to see the trans and try to control it. you'll need a computer from a 4.0 manual. (This was definitely true of newer years and not sure what auto we have in the mix from that early an exploder - A4LD?)

If you don't cross generations it is easier. 89-92 is 2nd gen, 94 is 3rd gen so yes you have a generation cross there... how much did they change in that generation change I don't know without both sitting in front of me. I "think" that is a plug and play swap.

Thankfully this exact and I mean exact swap has been done and documented... change the word ranger to bronco and you have a guide (94 auto into 89 manual):

1994 4.0L Auto Explorer To A 1989 2.9L Manual Bronco II - The Ranger Station

Original Poster: Dustin Ewers (disciplerocks) Difficulty: 8 out of 10 Time to install: 1-2 weeks+ (depending on skill and prep) Disclaimer: The Ranger Station.com, The Ranger Station.com Staff, nor the original poster is responsible for you doing this modification to … Continued

www.therangerstation.com

 

[SenorNoob]

94 Explorer was still the same body style as the 89 Ranger. There were a couple differences in the 4.0 from 90-94, but since it all came from the same truck a non-issue.

If it were mine, I'd try to just plug the BWP in and see what happens. I'd bet it just works except maybe a gauge.

The auto computer should work enough for you to drive it. (Assuming you get the clutch switch wired correctly for it to start.) I'd try to just unhook the 89 manual transmission sub-harness and plug it in to the 94 4.0 engine harness. It will keep the check engine light on and may cause idle problems. The idle strategy is different between auto and manual.

When you go to get a engine computer for 4.0 manual, make sure it's the same regarding EGR and injector wiring (SEFI or batch fire).

 

[Rjack90]

Well I ended up going to the junk yard and pulled the whole engine bay working harness out of a 91 4.0 ford ranger auto trans. The 60 pin connector was cut off so I had to solder on a new plug and pinned it accordingly to the diagram in the EVTM. Ordered a rebuilt CPU off parts geek for 91 ranger 4.0 manual trans and plugged everything in. All electric was plug and play very few places did I have to swap out connectors but was easy. I had to change out fuel lines to hook up but easy as well...
Hooked the battery up went to start and motor wouldnt crank. Jumped the starting Celinoid and it cranked but did not fire. Checked to see if I was getting spark and that was good. Checked fuel rail and no fuel.

pulled fuel line going to fuel pressure regulator and got a face full but it is not coming through. Possibly stuck shut fuel regulator? Worked 3 weeks ago on explorer

Other issues. No rear taillights or brake lights. Fan controls not working either. Possiblly more I haven’t discovered yet.

headlight, blinkers on front only, wiper and washer works.

With how well everything hooked up I was thinking it wa going to be turn key. Is it likely I got a bad cpu, how can I have that tested?

Any help would be much appreciated. I’m in southern Idaho, Buhl. If you know anyone close.
Thanks

 

[Brain75]

hazards on rear?
park lights on rear? (different circuit, different fuse, but same bulb and parallel wiring)

all of that lighting is body/fuse/switches - nothing under the hood as it were (sure the front lights are technically but aren't tied into anything you touched so shouldn't be affected).

having front turn means the fuse is good, my next step/question would be "were they working before" cause only couple places left are things you didn't touch (bulbs - both burnt out only the one filament, wiring from multifunction to tail, and multifunction itself).

sounds like the pump is running which eliminates the fuel pump relay and inertia switch.... I would hazard the filter or pressure regulator (or wiring/connector to it) I guess.

the CPU turns the fuel pump back on after the engine starts and gets to a minimal nothing RPM (like 350), but the prime should give you enough pressure at the rail to start and get to that point.

could also be a simple clog or you didn't burp out enough air to get the fuel all the way to the rail.

edit edit - misread the auto/manual - donor is auto edit: what about backup lights - since you got a donor manual harness you shouldn't even have any funny games to play with the backup switch etc - those I would think work right off.

 

[Rjack90]

No lights working on rear at all. Hazards work on front.
Everything was in working order 3 weeks ago when I pulled out 2.9. I have not touched anything for the dash. Just wired on the 60 pin connector for cpu.

 

[Rjack90]

With It not cranking when i turn the key I checked the red wire going to the s on celinoid and have no signal/ power

 

[Brain75]

the "60 pin" (sorry never counted em) is the computer connector in the passenger footwell, not the big white plug through firewall right?

 

[Rjack90]

correct 60 pin is cpu connector not firewall. I just plugged the firewall connector in

 

[Brain75]

and you spliced all 40-60 of the needed connections (I assume omitting ones said "not used")?

How confident are you in all of those - nice clean job on em all?

I can start a laundry list of all the things that might be keeping it from starting... and splicing all of those with no oopsies "I got the insulation jacket and not a solid connection" opens up a whole lot of lot.

could you share which pinout you used as a guide for the ones "not used" - I just want to make sure you got all the wiring solid before we start probing around rather then send you randomly all over.

 

[Brain75]

The igniton system fwiw - only 4 pins shown relevant coming out of the EEC-IV

https://www.therangerstation.com/tech_library/EDiagrams/files/Diagram_Ignition1990_4_0.JPG

differences in the EEC-IV pinout are kinda all over the place and some list pretty important stuff as "not used"
note the differences between these 2

Ford EEC-IV

Ford Technical Documents - www.fordmods.com

Ford Technical Documents - Ford Modifications Website

www.fordmods.com

 

[RobbieD]

I ended up going to the junk yard and pulled the whole engine bay working harness out of a 91 4.0 ford ranger auto trans.

I'd have to look at the diagrams, but on your "no start" condition I think the auto trans harness has a takeoff on the starter circuit after it comes through the firewall to run it down to the gear position sensor on the auto. If your truck was originally a manual, you should have the triple-function switch (clutch switch) already in place, and just need to jumper the auto harness.

 

[Rjack90]

Correct spliced and solder all wrapped in heat shrink. I am confident in the plug job. I used the plug from the 94 ford explorer so it was very straight forward. it even had the same color wires for 60% of it in the correct location. I soldered all like colors than organized the pin plug to match the chart.

 

[Rjack90]

See attached from 1991 ford ranger evtm 4.0

 

[Brain75]

I googled around a bit and a bent pin or dirty contact on the Big White Plug through the firewall seems to be the most likely for a whole lot - lights and starting included... since that is the only place the lighting circuits got touched at all that is where I would start.. should get backups, brake, turn and hazards all in one fell swoop there if you find it. (backups if your trans connector is solid too)...

Wire# Color Circuit
1 Red-White Temp Gauge to Temp Sending unit
2 Yellow-White Fuel Gauge to Fuel Gauge sender
3 White-Lt Blue Front Right Turn signal
4 Tan-Lt Green Anti Theft System switch feed
5 Lt Green-White Front Left Turn signal
6 Red Windshield Wiper Switch to Windshield Wiper motor
7 Purple-Orange Fused Run Only feed
8 Lt green Stoplamp switch to stoplamps
9 Dk Green-Lt Grn Shift on the fly 4x4
10 Pink-Lt Green EEC Module to Check Engine Lamp
11 not used
12 Tan-Yellow Ignition Coil negative terminal
13 Tan-Lt green Brake fluid switch to reservoir module
14 Gray-Red sensor signal return
15 not used
16 Black-White washer pump motor feed
17 purple-white dual brake switch indicator lamp
18 lt blue-orange O2 sensor feed - running only
19 not used
20 black-pink Windshield wiper switch to windshield wiper motor
21 dk blue-orange Windshield wiper switch to windshield wiper motor
22 white windshiled wiper switch to windshield wiper motor
23 tan-orange fog lamp switch to fog lamp
24 lt blue-black fog lamp switch to fog lamp relay
25 dark green failure warning light
26 lt blue-pink ABS control module feed
27 lt gray-orange Battery saver lamp feed
28 not used
29 not used
30 pink crank enable relay
31 white-red oil pressure indicator to oil press sending unit
32 light pink oil level relay to oil level sensor
33 not used
34 red-white electric t-case to manual level position sensor
35 lt green-black headlight dimmer switch to high beams
36 gray-white daytime running lamp
37 red-black headlight dimmer switch to low beams
38 lt blue-black brake feed
39 lt green-red igition switch "accessory" to alternator regulator "ign" terminal
40 lt blue-yellow manual level position sensor to EEC module
41 dk blue horn switch control
42 black-pink backup lamp
43 dk blue-yellow thermometer sensor feed
44 lt blue-orange ambient temp sensor to dash
45 orange battery feed to relay controller
46 brown headlamp switch to taillamps and side marker lamps
47 yellow-lt blue horn switch feed
48 black-white circuit breaker to seat latch relay
49 gray-lt blue htd backlite switch to time delay switch relay
50 yellow battery to load
51 brown switch feed
52 dk green power seat power feed
53 red-lt green ign sw to ign coil "batt" terminal

I got that off explorerforum - for a 1994 explorer

Edit: backups fixed after you get the auto trans connector sorted out with the manual wiring.