Engine harness

[Rollin]

Hello there,
I hope this isn't a dumb question but this Efi Ranger stuff is kinda new to me,
we just bought our 16yr daughter a 1990 ranger with blown motor 4.0L I happened to pick up a used 95 explorer motor but the engine harness is quit a bit different, do you see any reason I cant switch the one off the 90 onto the 95 motor and plug everything in and I am good to go.
I do no some about wiring--I just finished putting in a 95 mustang 5.0L into a 73 early bronco that had a in line 6 cyl. boy what a difference that made. I learned a lot on the way of transplanting it too.
Thanks
Mark

Oh ya a few threads down somebody is doing a 93 to 95 which seems about the same, should I just follow what they said???

 

[np24]

the engine is the same.
the only difference is that the newer engine will have a camshaft syncronizer in the back instead of just an oil pump drive assembly. you can swap the oil pump drive back in or just leave the syncro.
you will need to reuse your engine harness and any sensors that might be different. i can't remember if ford changed the connectors.

 

[Rollin]

Were is the oil pump drive at, on the 95 motor were there would be a dist. it has a sensor but the 90 is just block off with a plate.

 

[np24]

"the block off plate" is actually the oil pump drive. if you remove the clamp and rotate the engine, it should lift the assembly. i don't remember which way it has to go. it doesn't have to be timed to the engine, so don't worry about lining it up with anything when you put it back in.

 

[Rollin]

What about the fuel injectors and plastic intake, the 95 has red were the 90 looks like there just black with aluminum intake, do I need to change those as well or are they the same pressure?

 

[fireguy12117]

are you swapping PCM's?
right around those years they went from batch firing to sequential firing. the harnesses may be different in how the injectors are wired.

errrrrrrr...just re-read the OP. this wont apply as you sound like your keeping the old computer with the old harness. the motors are virtually the same barring whats been mentioned already. are they both EGR or non EGR motors? thats the only other thing i can think of at this point.

 

[AllanD]

No, the injectors are NOT the same.

You'll need to swap the injectors from the old engine onto the "new"
engine.

The "red top" injector aren't only a different flow rate
(the WRONG flow rate for your computer) they are a
different type (electronically) of injector

AD

 

[Rollin]

Ok, so it sounds like I should just think of the 95 motor as a long block and pull off everything and swap over all the stuff from the 90 motor.
One more thing, or maybe two or three---lol
what about the coil I guess youd call it that were the plug wires come out of
can I use the 95 or use the 90.
Is there a easy way to find out what tranny is in this 90 Ranger?
Thanks,
Mark

 

[AllanD]

Youl will NOT need to swap out the lower intake, or fuel rail infact you want to keep them because the lower intake and fuel rail are machined differently to allow for that 8mm plastic spacer.

In the mid 90's changes in federal law allowed the refineries to mix a higher
proportion of butane into winter mix gasoline (catalytic cracking process
produce a surplus of butane and propane), this is one of the reasons for
a loss of fuel economy on winter gas (butane has a slightly lower energy
content) which otherwise isn't a problem until you get that odd "Warm day"
on an early 4.0 engine and the heat from the engine boils the butane in the
fuel mix and causes a transient vapor lock condition.

Thermally isolating the fuel rail from the lower intake eliminated the problem

So remove the fuel rail and swap out the injectors and put it back together
the wayyou found it.

You'll also want to use YOUR aluminum upper intake and drivers side
exhaust manifold. to eliminate the EGR system that the later engine
was equipped with.

AD