[Gizzy]

Hello there,
I have an 87 YJ, I recently blew a rod through the engine block on my 2.5 engine, I have access now to a 92 2.5l engine, the difference is mine is throttle body injected and the 92 is multi port injection. I have the wiring harness and the computer off of the 92, I was wondering if anyonce can tell me of anything else I will need to swap in this engine. Also can anyone confirm that my tranny will bolt up to the 92, they both use the ax-5 and I am
%99 sure they will, But i just want to check before I get launched into the project.
My big concern right now is the fuel pump, will the one off of my engine work with the newer one?
thanks for any help, it is greatly appreciated.
also if anyone knows of a website that covers this, that would be awesome, i have done some searching, but have found little information on this
thanks again
Gizzy

 

[jeepinblackdog]

As long as you swap the harness and computer it should work fine. The transmission bolt up is the same and The fuel pump is the same as long as you old motor was a trottle body and not carberated.

 

[86Project]

Everything will work but you will have to change the fuel pump

Easiest way is to just get the tank off of the regular one. The reason being is the MPI always keeps a prime, if you have a Chilton or a Hanes just read about changing a fuel filter. Also your current fuel pump only puts around 6psi out under load where the MPI needs at least 19psi. Just can't be done with your current one.

 

[Boston Mangler]

Hey Gizzy

I was reasearching this extensively for my last Jeep and i pretty much got the same info. Here were some key notes

-Main thing is the CPS on the bellhousing, the MPI and the TBI using different ones, not sure on the mounting and if they mount in the same spot, but maybe you can get the bellhousing from the 92 to make sure!

-Fuel Pumps are different (easiest to use entire tank from the MPI vehicle with pump installed) that way its plug and play if your using that harness

-Make sure that puter is for a manual and not an auto

-If your 87 is vbelt (which i think it is) and you plan on keeping the Vbelt and swapping your stuff over, be careful with the waterpump, some are made to spin in the opposite direction (different impellor) for the serp belts

-If you plan on using the serp, make sure you have the proper waterpump for it! I know that the Vbelt pump and the Serp Pump SPIN opposite which WILL cause issues! They flow the same but spin opposite, due to the different belt routing!

-If your installing the 92, make sure you have the 92 computer for that rig, when i looked into this, certain years had some variations in the cams and using the wrong computer could cause problems!

-I am not sure if all the gauges "PLUG IN" to the new harness

-I dont think the airboxes interchange

-Now, with the MPI, you can rig up a check engine light, whereas the 87 dont have one, this is key because you can pull codes from it whereas you cant with the 87

-I believe the 92 is also OBDII or whatever its called and you can get a code scanner as well, not on the 87

Anyway, hopefully some of the above gibberish will help you, thats all i can think of now!

Best of luck

drop me an email, with any questions: [email protected]

 

[Mikel]

Re: Everything will work but you will have to change the fuel pump

The reason being is the MPI always keeps a prime

Why is this? I've had MPI vehicles that you can hear prime when you turn the ignition on, but my 92 Eclipse doesn't do that.
Thanks.
Mikel

 

[86Project]

Fuel rail

Not exactly sure but it has something to do with the fuel rail, I can find out, as a matter of fact I will and get back to you on it.

 

[86Project]

With the fuel rail it has to have gas at the top of the injectors in order to not allow air into the system with MPI it is very important to not allow air in, I can find out more if you need. Trevor

 

[Gizzy]

Hey thanks guys, that helps me out big time.