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Boneyard MPFI from 99 Cherokee

Boneyard MPFI from 99 Cherokee

cuban11182

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84 CJ7: 258, T5, Dana 300, Holley 390, Nutter Bypass.
I was talking with my father, and he informed me that he has a IM with the TB and injectors from a 99 Cherokee that came with the 4.0. From what I've read the MPFI is a bunch of sensors, the IM/injectors and the wiring harness. Is it possible to use that Intake Manifold and build a system? Does anyone know what all I would need?

Thanks,
Dave
 
I was talking with my father, and he informed me that he has a IM with the TB and injectors from a 99 Cherokee that came with the 4.0. From what I've read the MPFI is a bunch of sensors, the IM/injectors and the wiring harness. Is it possible to use that Intake Manifold and build a system? Does anyone know what all I would need?

Thanks,
Dave

First I have to ask what you mean by IM?

What are your plans? Are you retaining the stock engine in your cj? (is it a AMC 258 i6 / 4.2l or 4cyl?) will you be swapping out the complete block and using the 4.0 block? Which generation is the MPFI on it? I believe that in the beginning of the 99 year they still had a distributor and coil and later they switched to the COP (Coil over plug) design. What is your knowledge level of wiring an understanding wiring diagrams? If keeping a AMC 258 i6 / 4.2l bottom end are you going to swap a 4.0 head onto your engine or keep the AMC 258 i6 / 4.2l head? What alternator will you be using?

I can think of tons of questions that you may want to consider about MPFI before embarking on the swap. If you post up an idea of what you want your endstate to be you can get a lot more useful answers

Ideally the best setup is a complete 4.0 block, 4.0 head from a 91-95 (these still have the coolant temp sensor port in the back or the head for your gauge), and a wiring harness plus accessories from a 91-95 OBDI 4.0 as the wiring is less complicated and uses less sensors.

the 99 up OBDII has a lot more sensors, for example it has 3 or 4 O2 sensors where the obdI only has one.
 
First I have to ask what you mean by IM?

Sorry, that was military acronym kicking in, Intake Manifold

What are your plans? Are you retaining the stock engine in your cj? (is it a AMC 258 i6 / 4.2l or 4cyl?) will you be swapping out the complete block and using the 4.0 block?
Plans are to keep the stock AMC 258 i6 / 4.2l block and do a 4.0 head swap, comp cam, and either keep the 2150 with a clifford intake manifold or do some sort of FI.

Which generation is the MPFI on it? I believe that in the beginning of the 99 year they still had a distributor and coil and later they switched to the COP (Coil over plug) design.
Just called him and he verified that it was not the coil over plug design. It's either a 98 or 99.

What is your knowledge level of wiring an understanding wiring diagrams?
I am very comfortable with wiring diagrams and schematics. I have to read them for work from time to time (US Coast Guard).

If keeping a AMC 258 i6 / 4.2l bottom end are you going to swap a 4.0 head onto your engine or keep the AMC 258 i6 / 4.2l head?
More than likely swap to a 4.0 head.

What alternator will you be using?
Didn't know this was something to address. I had planned on getting a new one when I do the rebuild, what are the alternatives to the stock alternator.

I can think of tons of questions that you may want to consider about MPFI before embarking on the swap. If you post up an idea of what you want your endstate to be you can get a lot more useful answers

Ideally the best setup is a complete 4.0 block, 4.0 head from a 91-95 (these still have the coolant temp sensor port in the back or the head for your gauge), and a wiring harness plus accessories from a 91-95 OBDI 4.0 as the wiring is less complicated and uses less sensors.

the 99 up OBDII has a lot more sensors, for example it has 3 or 4 O2 sensors where the obdI only has one.

Makes sense. Two for checking actual AFR and two to check after the CAT to make sure it is doing it's job.
 
First I have to ask what you mean by IM?

Sorry, that was military acronym kicking in, Intake Manifold

What are your plans? Are you retaining the stock engine in your cj? (is it a AMC 258 i6 / 4.2l or 4cyl?) will you be swapping out the complete block and using the 4.0 block?
Plans are to keep the stock AMC 258 i6 / 4.2l block and do a 4.0 head swap, comp cam, and either keep the 2150 with a clifford intake manifold or do some sort of FI.

Which generation is the MPFI on it? I believe that in the beginning of the 99 year they still had a distributor and coil and later they switched to the COP (Coil over plug) design.
Just called him and he verified that it was not the coil over plug design. It's either a 98 or 99.

What is your knowledge level of wiring an understanding wiring diagrams?
I am very comfortable with wiring diagrams and schematics. I have to read them for work from time to time (US Coast Guard).

If keeping a AMC 258 i6 / 4.2l bottom end are you going to swap a 4.0 head onto your engine or keep the AMC 258 i6 / 4.2l head?
More than likely swap to a 4.0 head.

What alternator will you be using?
Didn't know this was something to address. I had planned on getting a new one when I do the rebuild, what are the alternatives to the stock alternator.

I can think of tons of questions that you may want to consider about MPFI before embarking on the swap. If you post up an idea of what you want your endstate to be you can get a lot more useful answers

Ideally the best setup is a complete 4.0 block, 4.0 head from a 91-95 (these still have the coolant temp sensor port in the back or the head for your gauge), and a wiring harness plus accessories from a 91-95 OBDI 4.0 as the wiring is less complicated and uses less sensors.

the 99 up OBDII has a lot more sensors, for example it has 3 or 4 O2 sensors where the obdI only has one.

Makes sense. Two for checking actual AFR and two to check after the CAT to make sure it is doing it's job.

I specialize in the OBDI conversions so if you attempt to use the OBDII get in touch with me and I would be glad to work with you directly as I have been wanted to expand into OBDII harness conversions I just have needed to find someone doing it or purchase a jeep with a AMC 258 i6 / 4.2l or 4.0 to try it in.

I eventually want to do 99+ COP conversion harnesses.
 

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