4V swap. Harness or PCM

[maximusslade]

I'll keep the question short. I am doing a 4V swap into my P71. If you guys were doing it, would you rather alter the harness or would you rather just swap out the PCM? I would have to get a tune either way.

[mattdohc]

just alter your cv harness. I just did this to my 03 lx sport.

[Bad_S55]

Rewire the stock harness & get a tune. That's it.

[Chayton]

im putting a 98 4v in my 02 crown vic sport. I read something about the fuel systems being different?

[massacre]

What car is the 4v from?

[maximusslade]

Click the link in my sig... but in short, it is a '98 MkVIII block, '01 Cobra heads, '03 Marauder intake.

[massacre]

Is the ECM return style or returnless? That is what will dictate which fuel rail to use.

[maximusslade]

Both fuel systems are returnless... but what bearing does that have on whether to splice the wiring harness or use the marauder PCM

[Chayton]

Both fuel systems are returnless... but what bearing does that have on whether to splice the wiring harness or use the marauder PCM

hes talking to me.

[maximusslade]

Oh.. okay... I think both the '98 and the '02 are both systems that have fuel returns. I would surmise they are the same system, so long as you are using the '98 4v fuel system.

[Zack]

Both fuel systems are returnless... but what bearing does that have on whether to splice the wiring harness or use the marauder PCM

WRONG
The end

[Zack]

The pcm is programmable for either type of fuel system

[Chayton]

WRONG
The end

which one is which?

[Zack]

If you are swapping engines, I suggest you do more research.


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[maximusslade]

Okay... we need to back up a few steps here gents. *I* am not asking about the fuel system. I am asking as to whether it is simpler to splice wiring or go with a Marauder PCM in a Vic...

Before someone starts spouting of the ever useful one word answer, let's make sure we are answering the question asked...

[Chayton]

If you are swapping engines, I suggest you do more research.


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lol. classic zack!

[Chayton]

Okay... we need to back up a few steps here gents. *I* am not asking about the fuel system. I am asking as to whether it is simpler to splice wiring or go with a Marauder PCM in a Vic...

Before someone starts spouting of the ever useful one word answer, let's make sure we are answering the question asked...

Yeah sorry for hijacking your thread bro. From my understanding it is suggested to modify your stock wiring. Seems you are a lot deeper in this that I am, I will definitely be referring to your thread along the way of my build.

[Zack]

This is monumentally simple.
Obtain PCM pinouts for both pcm's
Find differences, which will be very minimal.
Move wires around in the appropriate connectors.

Do research on reversing the wires on the coil packs so they work properly

[sexygomer]

Just did an '04 Vic. Wiring is the same, some connectors (COP, TPS, Idle control) need to be lengthened. I found a schematic that showed the COPs to be reverse polarity, however, I later discovered this was wrong. Although it could be the case for older/newer vics. I'll try and remember what else I had to modify, but really, it was actually pretty easy. I will add that if you use a teksid block, there are two bungs for knock sensors and the iron block only has one and the thread size is way different.

[maximusslade]

I will add that if you use a teksid block, there are two bungs for knock sensors and the iron block only has one and the thread size is way different.http://www.mercurymarauder.net/forums/images/buttons/quote.gif (http://www.mercurymarauder.net/forums/newreply.php?do=newreply&p=1525404)

Yes, I have found that. I am going to have to be a tad inventive to make it work.

[massacre]

Sorry about the fuel rail comment, yes use the 2V computer and modify harness as needed.

[hotford]

This is monumentally simple.
Obtain PCM pinouts for both pcm's
Find differences, which will be very minimal.
Move wires around in the appropriate connectors.

Do research on reversing the wires on the coil packs so they work properly

^^^^^^^^^^^Do exactly what he said^^^^^^^^^

[maximusslade]

Wait wait wait! I should have asked... I already have TWO Marauder engine harnesses. Might it be simpler to use those? Changing the pin outs as needed at the PCM connecter?

[Zack]

You will have to verify all bulkhead connectors are wired appropriately

[mattdohc]

Wait wait wait! I should have asked... I already have TWO Marauder engine harnesses. Might it be simpler to use those? Changing the pin outs as needed at the PCM connecter?
just mod your stock harness. that's what I did mine is running and driven with out a tune. im running 91 octane. and yes im going to get a tune. it will need it to run the way its suppose to. I did mark viii block with marauder heads and intake. but my car is an 03. no return fuel system.

[Serge]

Just mod the Vic harness. Have to change COP connectors and extend a couple other sensors.

Return or returnless fuel system doesn't make much difference. Vic PCM can be tuned to run either. I have 03' Vic PCM in my box and I am running return fuel system.

[maximusslade]

Sooooooo. Another issue stemming from this. I have COPs from the Continental I got the heads from. I hadn't bothered looking into getting new coils because I thought I have some. Turns out that the Marauder harness will not plug into the Continental coils. Seems the little alignment tabs are different. Now I have the connectors from the Continental that I can use. The question I have is, other than the connector, how different is the continental cop from those of the Marauder? Are they of the swapped polarity as you guys say the Marauder coils are?



I'd hate to have to buy new coils if the ones I have are in good shape.

[maximusslade]

Okay... looking at this a bit... I have the Continental COP connectors. I have Marauder wiring harness. Seems the logical and least expensive option is to keep the Continential coils and connectors and then splice those into the native CVPI engine harness.

BUUUUUUUUUUUUUUUUUUUUUUUUUUUUU UUUUUUUT.... Looking at RockAuto.com... the 2001 Continential and 2003 Marauder use the same coils. I am looking at the Motorcraft site and still they list the same 12029 part number, yet the Continential coil does not plug into the Marauder harness...

[Zack]

Get the proper coils

[SteelQualityMan]

Okay... looking at this a bit... I have the Continental COP connectors. I have Marauder wiring harness. Seems the logical and least expensive option is to keep the Continential coils and connectors and then splice those into the native CVPI engine harness.

BUUUUUUUUUUUUUUUUUUUUUUUUUUUUU UUUUUUUT.... Looking at RockAuto.com... the 2001 Continential and 2003 Marauder use the same coils. I am looking at the Motorcraft site and still they list the same 12029 part number, yet the Continential coil does not plug into the Marauder harness...

I have an 01 CV and I'm thinking about doing exactly what you are doing with yours. Can you post about problems you run into and hopefully include some pictures?


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[justbob]

Why splice them? Simply de pin them if needed.


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[maximusslade]

Why splice them? Simply de pin them if needed.



Because the continental connectors are already cut.

[justbob]

Because the continental connectors are already cut.



Figured that much. That's why I said to de pin them and plug the pins of the harness you choose into them. Unless you don't mind sixteen splices.


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[maximusslade]

Got a line on the tools needed for that? I thought the pins were molded into the plugs?

[Zack]

Got a line on the tools needed for that? I thought the pins were molded into the plugs?

A pick

67890

[Turbov6Bryan]

If you don't have the tool, sometimes a really small zip tie fits in there to release the tang that holds the wire in place. Or a small paper clip

[justbob]

A pick



67890



You owe me a coffee!


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[massacre]

Remove the lock to expose the tabs to remove the pins. I made a thread on it on PBB. I would link it but am unable to at this time. If you are using stock 2v harness you would have to re-pin anyways.
Tiny flathead screwdriver will do it