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PI Intake Manifold Swap

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    PI Intake Manifold Swap

    (This will be edited over the course of the week, because I don't have the time to do this write up in one sitting)

    This write involves everything that entails installing a Perfomance Improved (PI) Intake Manifold on a Non-Performance Improved (NPI) engine.
    First, this write up is aimed at the 92-95 NPI engines.
    Secondly, this swap will be much easier for the 96+ crowd. Mainly, because you do not have to modify the engine harness.
    To start things off, here is a list of parts you will need. All the items that are bold are REQUIRED for both 92-95 and 96+ systems.

    Parts List:
    - PI Intake Manifold (any PI will work; I used a FRPP unit from a 04 Mustang GT)
    - PI Intake Manifold Gaskets(kit includes upper plenum gasket)
    - Upper Intake Plenum
    - Throttle body
    - Idle Air Control (IAC) Valve
    - Air Intake
    - 96-97 Fuel Rail
    - PI Heater Core Return Line
    - PI Water Pump Inlet Nipple
    - 96-97 Spark Plug Wire Bracket
    - Water Pump O-ring
    - IAC Gasket
    - Throttle Body Gasket
    - Thermostat Housing O-Ring
    - 96+ Throttle Cable
    - 96+ Throttle Cable Bracket with spring
    - Fuel Injectors (Skinny)
    - Fuel Injector O-Rings (16)
    - 96+ vacuum lines. All of them.
    - Save as much harware from the junkyard as possible.

    - Blue RTV
    - 1 gallon of coolant. I use the straight glycol and mix it myself. I see 50/50 as a waste of money.
    - Brake cleaner
    - Paper towels
    - Beer

    Specialty Tools:
    - Fuel rail disconnect kit
    - Mechanical fan removal kit- I forgot that most people have this still installed.

    This will take a while. So don't plan on having your car for a solid weekend. It will not take 4 hours. It may take your less or more time depending on your mechanical ability and how much other maintenance you would like to get done while you have parts off your car.

    Find a suitible vehicle to do the swap!

    You don't have to do this, but I removed the hood for A. more light B. less hitting my head and C. more room.


    Disconnect the battery. (Another option. I removed the battery because I needed to install and new one.)

    Put a suitable containter under the radiator on the drivers side. Open the petcock and start to drain the coolant.

    Disconnect the Intake Air Temperature (IAT) Sensor and the Mass Air Flow (MAF) Sensor and remove the air intake.

    Pop off the throttle cable with a flat screwdriver, and remove the 4 8mm bolts to remove the throttle body. Set the throttle cable to side on the drivers side inner fender area.

    By now, there should be enough coolant drained to reposition the radiator return line. To keep the mess down, I loosened the clamp from the thermostat housing, the loosened the clamp on the radiator and rotated the hose over to the power steering reservoir. The same applies to the coolant line that goes to the heater core from the intake manifold. Disconnect it from the manifold and rotate it upwards to keep the mess down. (I remove and replaced mine with CVPI silicone hoses)

    I realize that not every car has the mechanical fan removed like the Tank. Use the mechnical fan removal tool(s), loosen the fan. Remove the 4? bolts that hold in the fan shroud. Then remove the shroud and fan assembly.

    IMPORTANT!- use a ratchet or an impact ratchet and loosen the 4 10mm bolts on the water pump pulley. DO NOT REMOVE THE PULLEY UNTIL THE BELT HAS BEEN REMOVED!

    Disconnect all the sensors and start to remove the engine harness. On the drivers side, underneath, you do not have to disconnect the Oil Pressure Sensor or the Power Steering Pump Speed Valve Sensor. They may remained connected.
    Start on the passenger side. Underneath, disconnect the Crank Position Sensor (CPS) and the Air Conditioning Clutch plug. Then, disconnect the Alternator Charge cable to the Distribution Box. Disconnect the coil pack, emissions, fuel injector wiring( 92-95- Label each injectors position. Wrap a slice of duct tape on it and write # 1-8 on each connector for it's coresponding cylinder number. The engine harness needs to be broken free of the stupid plastic piece that holds it all together on top of the intake manifold. You don't want to spend time trying to figure out which injector harness goes where), alternator wires, and coolant sensor to the harness.
    -92-95 Disconnect the vacuum line to the intake plenum. then remove the braket on the backside (2 8mm bolts)<--8mm ratcheting wrench will save you]. Then remove the 4 8mm bolts and remove the intake plenum assembly.

    Then make your way disconnecting everything around the back of the motor. the O2 Sensors are hooked up to the engine harness, so they may be a bit difficult to get to. Step 9.1 makes this easier for the 92-95.
    Remove the connection to the IAC, Throttle Position Sensor (TPS), Exhaust Gas Recirculate (EGR) Valve and sensor. Then the drivers side fuel injectors, coil pack, camshaft sesnor, and coolant sensor. Lastly, disconnect the engine harness from the connection that goes to the Powertrain Control Mondule (PCM). It's located unter the brake master cylinder and requires the loosening of one 10mm bolt. Then carefully removed the connector and lay the entire harness on the drivers side fender/area.
    Also, remove the vacuum lines as well during this time.

    Use a 1/2" drive breaker bar (or equivilant) and relieve pressure on the tensioner and remove the accessory belt. Replace if necessary.

    Remove the 3 8mm bolts and the 2 10mm bolts, then remove the alternator.

    By now, the coolant should be mostly drained via the petcock. Close the petcock, and move the container under the water pump. Remove the loosened 4 10mm bolts, remove the pulley, then remove the 5 13mm bolts that hold the water pump, and remove the water pump.

    Using the fuel line disconnect tool, disconnect the two fittings that connect to the fuel rail. Take a small piece of mechanics wire/saftey wire/zip tie/string and tie the to the cap on the brake reservoir. This will keep them out of the way, and spilling gasoline and making more of a mess.
    Remove the 4 8mm bolts and remove the fuel rail and the injectors.
    --edit image-----

    Remove the 11 10mm bolts that hold the intake to the heads. Although it is aluminum, it weighes roughly 30 lbs, so be prepared for it, especially because Panthers are so wide.
    I kept the bolts in order for reinstalltion.

    Intake removed:

    Another look, showing the Heater Core Return Line that needs to be replaced/put out of its misery.

    And the blown out intake manifold gasket on the drivers side. This is the whole reason this swap is going on.

    Disconnect the bonding wire from the back of the engine and remove the old Heater Core Return line.
    The return line has to be changed out because the PI Intake manifold is so big, that the line interferes with the manifold laying flush. The line and the nipple that it connects to on the back of the water pump must be replaced with a PI version.

    Using a ball peen hammer, gently tap out the old nipple on the back the water pump.

    Use a deep well socket (I used an 11mm. It worked out that way) and tap the new nipple into place. I put a small amount of Blue RTV around the lip of the nipple where it mates to the block to prevent any leaking.

    Newly installed.

    Install the PI Water tube.

    Another view:

    Don't forget to reconnect the bonding wire. I moved my drivetrain grounding wire from the transmission case to the back of the head for easier accessibility.

    Reinstall the water pump. Don't forget the new O-ring. The old O-ring expands too much and you cannot reuse it. I also put a small bit of Blue RTV around the edge of it to prevent leaking. Temp install the pulley with 4 10mm bolts. Note: Powdercoated Satin Black bolts

    Remove the old intake gaskets and clean up the mating surfaces. Put paper towels or rags in each cylinder to prevent Foreign Object Debris (FOD) from entering the cylinder. As I wall putting a paper towle into #1, a piece of old conduit went into the head. It's a good thing I have a sweet pair of loooong needle nose pliers.

    This is where it gets fun.
    Set the PI Intake Manifold on the engine.
    --*92-95*-- Now it's time to break apart the old stupid plastic wire loom. You can break it apart by hand, because after 20 years of use, it's quite brittle.
    Lay out the wiring, and start making new wiring looms. Use plastic conduit and make the passenger side fuel injector harnesses.

    Also temporarilly install the alternator and the fuel injectors to make sure you have all the wiring in the correct order. I also temp installed the upper intake plenum to make sure the harness was going to fit underneath it.
    -92-95 Modify the IAC wiring:
    --Because the IAC is relocated from underneath the manifold to the side of the upper plenum, the wiring has to be extended. You may reuse the old IAC, but I opted for a newer one, and to make mine a little more colorful.
    There are only two wires to extened. Cut the two wires going to the IAC. Connenct the red wire from the harness to the red wire of the NEW connector. And connector the other wire, white/blue, to the other remaining wire; white/orange.

    -92-95 Extend the DFPE wiring:
    -- the DFPE sensor is moved from the back of the intake plenum to the throttle bracket on the upper plenum. I just cut, and extended the wiring about 10" and reused the original sensor and connector.

    Here is the finished product. This should give you some idea on how it should look.

    Remove all of the temp installed items from the previous step (Alternator, upper plenum, injectors and PI Intake Manifold)

    *92-95* Remove the 2 11mm nuts on the firewall for the throttle cable. Then, disconnect the throttle cable from the back of the gas pedal, and pop off the large metal clip above the gas pedal that holds the throttle cable.
    Remove the entire throttle cable assembly.

    *92-95* Install the new throttle cable. Mount it to the firewall with the 2 11mm nuts. Reconnect to the gas pedal and reinstall the large metal clip. Let the throttle cable lay in the inner fender area o nthe drivers side.

    Test fit the PI gaskets. I found that the dowels on the gaskets are opposite the holes on the NPI heads. Not even close.
    So I carefully removed the alignment dowels from the gaskets with a Dremel. Then, set them down on the heads to ensure that they will sit flat and flush.
    *** Put Blue RTV around the water jacekts on the gasket. They are slighty different and may leak if you do not put Blue RTV on it.***

    Install the PI intake Manifold. Then install the thermostat O-ring and thermostat, then install the thermostat housing.
    Torque all bolts inthe correct tightening sequence to 15-22ft/lbs.

    Another view:


    Install new O-rings on the injectors and reinstall the injectors.

    Note: I used the "skinny" injectors because I got a great deal on them. They hook right up to the harness.

    Install the new 96+ fuel rail. Install the 4 8mm bolts and reconnect the fuel lines.

    Start reconnecting the engine harness.

    Reinstall the alternator and reconnect the alternator wiring.

    Reinstall the accessory belt.

    Reinstall the mechanical fan and the fan shroud.

    Reconnect the radiator return line to the thermostat housing.

    I installed the new IAC (with new gasket) and EGR block off plate(with new gasket) while the upper plenum was sitting on the bench.
    -->The 92-95 Panthers require 6 vacuum lines,and the 96+ require 7 vacuum lines. I capped one vacuum line. Eventually, I will use that extra vacuum line as a pick up for the vaccum gauge.

    Then, install the upper plenum with 5 8mm bolts.

    Another view:

    Install the throttle cable bracket with the DFPE sensor. Then connect all the vacuum lines to their applicable locations. The IAC and drivers side PCV can wait until the air intake is installed.

    Install the throttle body, with a new gasket. You can reuse the old throttle body, but you have to swap out the linkage with a 96+ because the 92-95's pull from the the front of the throttle body, and the 96+ pull from the rear. Plus, the ends of the throttle cables are different. It's just much easier to get a 96+.

    Facing the throttle body:

    Connect the new throttle cable. Do not forget to install the spring.

    Side view:

    Install the 96+ spark plug wire loom. Connect the spark plug wires to the loom, and install the bolts to secure the alternator.

    Install the air intake and hook up the required vacuum lines.

    Vacuum lines:

    Install the MAF housing .

    Here's where it varies. I had an aluminum intake installed, and there was spot tapped out for the IAT sensor. Normally, they are located in the air box, which I do not have. I drilled out a hole in the air intake, and mounted the IAT there.
    Also, I have a MAF adapter to mount a concial filter on the end of my air intake system.

    I had to use the filter from my old 1998 SVT Countour. It was the only one that would mount to the MAF adapter correctly.

    Start filling up the coolant reservoir.

    Reconnect the battery.

    Turn the key to the "ON" position a few times to cycle the fuel pump and build up pressure.

    Start your engine! Be on the look out for leaks and bad noises (you know exactly what I'm talking about). Don't let it run for too long, because there isn't enough coolant in it. It took me 4 tries to get the coolant level up to the correct levels.

    As long as there are no fluid or vacuum leaks, and the vehicle runs fine, time to take a test drive! You should notice a difference in the mid to upper RPM range.

    Win. Crack open a celebratory* beer and enjoy the success!

    During this time, there are many options available. Upgrading water pumps, fuel injectors, upper plenums, throttle bodies, intakes, spark plugs and wires and so forth.
    I did this swap because I had a blown intake manifol gasket, and because I'm planning on swapping in PI heads/engine soon. This intake swap would allow me to simply disconnect everything and go about the engine install. This way, if something goes wrong with the engine install, I can locate the problem easier.

    -ryan s.
    Last edited by SVT98t; 03-25-2013, 02:02 PM. Reason: Bi-Winning
    08 Lincoln Navigator L - 233k
    03 Mercury Marauder- 63k
    97 Ford Crown Victoria HPP "Tank of Justice III" (TOJ3) - 194k -->578.9 miles on ONE tank of gas<--
    94 BMW 325i Convertible - 135k
    73 VW Super Beetle "Bunky" <----- Wifey's
    12 Mini Cooper S - 90k <---- Wifey's
    Originally posted by pantera77
    Well my buddy tells him he knows exactly who loves buying shitboxes.

    Woo Hoo! Thanks for taking the time to work on this.
    Looking forward to it.
    1997 MGM (bought for a song) MODS: New 70mm MAF, True Duals w/ GlassPacks, 70mm TB, Full custom CAI w/ Cone Filter, SCT tune, Marauder 21mm rear sway, Moog end links, 29mm CVPI front sway, Trak Loc posi w/ 3:55's.

    On The List: JMod, PI Intake, Ported Plenum, TB spacer (maybe) Fatter Tires for summer, HD Cop Shocks, Rims, and hopefully new green skin.


      Outstanding job with pictures and details


        Nice work and EXCELLENT documentation!! Bobby

        "Hope and dignity are two things NO ONE can take away from you - you have to relinquish them on your own" Miamibob

        "NEVER trade your passion for glory"!! Sal "the Bard" (Dear Old Dad!)

        "Cars are for driving - PERIOD! I DON'T TEXT, TWEET OR TWERK!!!!"


          Wow, very nice write up mang!

          1981 Mercury Marquis Brougham 2-Door 302/ 5-speed -special blend (GMGT)
          1987 Lincoln Mark VII 5-speed (Errand runner)
          1989 Mercury Grand Marquis (Base Runner)
          2007 Lincoln Town Car Signature Limited (Hustlyn)
          2011 Ford Crown Victoria Police Interceptor (Down with O.P.P)


            Chris Fix did a video of this on a Mustang. Just in case someone wants a video to look at.

            Only two things are infinite, the universe and human stupidity, and I'm not sure about the former. -- Albert Einstein
            rides: 93 Crown Vic LX (The Red Velvet Cake), 2000 Crown Vic base model (Sandy), 2003 Expedition (the vacation beast)

            Originally posted by gadget73
            ... and it should all work like magic and unicorns and stuff.

            Originally posted by dmccaig
            Overhead, some poor bastards are flying in airplanes.


              Hah, I saw that yesterday and came here to post it. Nevermind
              1985 LTD Crown Victoria - SOLD
              1988 Town Car Signature - Current Party Barge


                For those thinking about doing a PI intake swap, I will note that you should also consider porting and polishing the plenum and swapping the 65mm throttle body for a 70mm throttle body. You can also consider swapping the NPI camshafts for PI camshafts, though I'm not sure how far back that swap will work.

                For those with premature timing chain tensioner arm wear in "some" 2000 panthers, changing the tensioner stuff would provide an ideal time for doing both the PI intake swap and the PI camshaft swap. (The tensioner issue is actually for "some" 2000-2003 panthers, but 2001+ are already PI.)

                Back before I knew about all this stuff, I had replaced the all-plastic NPI intake manifold in my 2000 MGM with an upgraded NPI intake manifold (with the aluminum crossover), though I did put on a 70mm throttle body subsequently since it was so convenient. It made a noticeable difference for me. I haven't had obvious problems with my tensioner stuff yet, but I've been preparing for it. Considering that the Chris Fix video only shows an improvement in the high RPM range for the PI intake manifold by itself, and that I generally don't drive in the high RPM range, I'm not in a rush to do the PI intake swap. What I would be interested in knowing at this point though is whether doing the PI camshaft swap at the same time will have any benefit in a lower RPM range. Any ideas?
                Last edited by IPreferDIY; 07-14-2018, 04:22 PM.

                2000 Grand Marquis LS HPP, a hand-me-down in 2008 with 128,000 km; 175,000 km as of July 2014
                mods: air filter box 'tuba', headlight relay harness, J-mod (around 186,350 km), 70mm throttle body, KYB Gas-A-Just shocks, aluminum driveshaft, ARA3 PCM


                  Does anyone know about year-to-year variations for the heater pipe nipple, the heater pipe, the heater hoses, and the intake manifold gaskets?

                  1. heater pipe nipple - I know that the nipple for the older NPI heater pipe with a piece of hose on the end has to be changed, but I think I saw something once about differences in the nipple even if you have a newer NPI heater pipe that does not have the piece of hose.

                  2. heater pipe and hoses - They changed the style of the PI heater pipe in 2003. From what I can see in photos (I used two Dorman photos below since RockAuto does not have the later Motorcraft pipe), the bending is different, and the bracket for the bolt is in a different direction. Will the 2003+ still work with 2000- or are we stuck with 2001-2002? And is there a corresponding difference in heater hoses?

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                  3. intake manifold gaskets - They changed the style of the PI intake manifold gaskets in 2004, though from what I can see in photos, it's merely slight changes in the plastic on the ends that would not seem to have any significant effect. Since the intake manifold is the same for 2001+, I don't see what significance there would be (apart from the 2001-2003 gaskets having a lower price). Is there any significance?

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                  2000 Grand Marquis LS HPP, a hand-me-down in 2008 with 128,000 km; 175,000 km as of July 2014
                  mods: air filter box 'tuba', headlight relay harness, J-mod (around 186,350 km), 70mm throttle body, KYB Gas-A-Just shocks, aluminum driveshaft, ARA3 PCM


                    Hadn't noticed the difference in the intake gaskets. There was a casting revision in the PI heads mid 2004, it is the same time that they finally fixed the "there's only 4 threads holding my spark plug into the cast aluminum head" problem. Perhaps they also moved the alignment holes for the intake gasket to slot into? That is the only reason I can think that they'd change the gasket since the manifolds are the same.

                    Heater pipe probably changed in 2003 because '03+ have a foam insulator around the bottom of the intake. It could also be because they moved the EGR tube in 2003 and IIRC the earlier tubes shared a bracket with the tube. Either way, I dunno how much it matters because its still gonna take the water bypass from the same spot on the backside of the water pump, around the same intake manifold, and out the backside of the motor where it connects to a heater core hose in roughly the same spot as any other bypass tube on a 4.6, it just takes a different path to get there.

                    This is something that I'm planning for my '98. I'm confident in the job cuz its far from my first 4.6 intake replacement, also its a '98 so aside from the gaskets and under-intake tube modifications its a pretty direct swap. Just debating on painting it first. For all of my cars I've had a plenum/TB painted in "cast aluminum" on top of the plastic mani, might wanna switch that around and paint the plastic "cast aluminum" and the plenum black just because its a different look on a 4.6.
                    Last edited by BigMerc96; 08-20-2018, 09:17 AM.

                    2006 Audi A6 S-Line FWD ~132k miles, stock.
                    1998 Mercury Grand Marquis LS HPP ~102k miles, slowly acquiring modifications.
                    1997 Lincoln Town Car Cartier ~145k miles, Ported Plenum, Gutted Airbox, Mechanical Fan Delete, Contour E-fan Retrofit, Dual exhaust, Cats ran away, KYB Gas-A-Justs, P71 front sway bar, air ride reinstalled, Blinker Mod, Projector headlight retrofit, Caddy 4-note horn retrofit, Wood rim steering wheel, rustbelt diet plan..
                    1996 Mercury Grand Marquis GS 117,485mi. R.I.P. 7/14/12


                      The alignment nubs on the gasket seem to be in the same spots. They'd have to come off for the swap anyway, so that wouldn't be a big deal. The only difference I can see is the plastic on the ends, and I can't imagine what relevance that might have. I ended up making the presumably dumb mistake awhile ago of getting the Mahle 2004+ gaskets from RockAuto at a clearance price that was about double their clearance price for the Mahle 2001-2003 gaskets, but if they work, then meh.

                      The insulator explanation for the heater pipe is interesting. I recall one explanation for the insulator being the introduction of a knock sensor in 2003. Another explanation was keeping heat away from the plastic, though I'm not sure that would make a big difference. Engine noise might be lessened, though that in itself would not be an issue for me. In any event, the two decent used IMs I grabbed had good insulators, so I'd be inclined to use them. It looks like the later pipes are cheaper too. I wouldn't rule out trying a used one if I happen to find one in really good shape, but since they're prone to developing problems, I would put a coat of high heat paint on whatever I get, whether used or new.

                      2000 Grand Marquis LS HPP, a hand-me-down in 2008 with 128,000 km; 175,000 km as of July 2014
                      mods: air filter box 'tuba', headlight relay harness, J-mod (around 186,350 km), 70mm throttle body, KYB Gas-A-Just shocks, aluminum driveshaft, ARA3 PCM