How to: - Starting my 00M12 Installation | Ford Explorer Forums - Serious Explorations

  • Register Today It's free!

How to: Starting my 00M12 Installation

Prefix for threads which are instructional.


Moderator Emeritus
May 26, 2009
Reaction score
City, State
Greenville, SC
Year, Model & Trim Level
00 Sport FI, 03 Ltd V8
My cold weather start up flare has increased to more than 2,000 rpm and the chain rattle is very loud for about 5 seconds until the oil gets to the chain. I decided I can't delay the tensioner and gasket replacement any longer. I ordered Ford part number YL-2Z-9E473-AA from for $49.49 plus shipping (also available from and for about the same price). The kit should be here tomorrow. Since I limit the time I work on my Sport to 2 hours per day I hope to have the upper and lower intake manifolds removed and cleaned by Sunday. I have a lot of carbon build up in the upper intake plenum and probably as much or more in the lower intake manifold. I've printed out the excellent post by mikeh 98 SOHC Cold Start Idle problem to use as a guide and will take photos during disassembly so I can refer to them during reassembly.

Join the Elite Explorers for $20 each year.
Elite Explorer members see no advertisements, no banner ads, no double underlined links,.
Add an avatar, upload photo attachments, and more!

Removing upper intake manifold

Here are some notes and photos I made while removing the upper intake manifold to supplement mikeh's excellent instructions:

Disconnect the battery

Removing the throttle body allows observation of the EGR tube which may be in very bad condition.

The plastic clip retaining the hose connection under the intake manifold on the passenger side is easier to remove after the torx screws are removed so the manifold can be moved upward to get room for your hand

Disconnect the 3 spark plug wires attached to the rear of the manifold.

There are 8 torx screws attaching the manifold. The rear ones (hardest to remove) should be removed first. That way the other screws will hold the manifold in position and prevent binding on the rear ones. If you don't have a 1/4 inch drive with a flexible joint or an allen shape you will not be able to extract the rear screws without disconnecting the PCM and moving the harness out of the way. The photo below shows the location of the rear screw on the driver side and a 3/8 inch drive with 1/4 reducer for the Torx bit.

As the screw is removed the drive bit with adaper interferes with the wiring harness. My 1/4 extensions were either too long to fit under the cowling or too short to clear the PCM harness. The photo below shows how much easier things are after disconnecting the PCM connector and moving the harness to the side.

There is also an interference problem with the rear torx screw on the passenger side shown in the photo below.

Moving the harness aside simplifies removal (still an aggravation).

Disconnect the electrical and vacuum connections to the EGR vacuum regulator shown in the photo below.

I did not complete the removal of the upper intake manifold in the first 2 hour workday. The EGR tube was binding on the manifold (there is extensive carbon buildup) and I was afraid to force things and possibly damage whatever seals the tube where it enters the manifold and prevents air leaking around it into the manifold.

Inspecting upper intake manifold

I continued to wiggle, twist and pull the upper intake manifold upward and toward the passenger side until I finally worked it free of the EGR tube. The photo below shows the bottom of the manifold.

There is extensive carbon buildup in the tubes which can be seen in more detail in the closeup below.

It will take several hours to clean the internal airflow paths of the manifold.
The photo below shows the top of the upper intake manifold.

The IAC valve bolts to a plastic part that is attached to the manifold. It is shown better in the closeup below.

Later during reassembly I will remove the 4 bolts and see if there is a gasket to prevent air from entering the manifold.

Be sure you stuff shop towels into the openings to prevent anything from falling in...

I was debating on tackling this job myself, then opted for a mechanic to come out & do it at my house... I specifically told him to block all openings.. long story short, he dropped a bolt in the motor.

Rebuild should be done by Monday... $2,200.


Be sure you stuff shop towels into the openings to prevent anything from falling in...

I was debating on tackling this job myself, then opted for a mechanic to come out & do it at my house... I specifically told him to block all openings.. long story short, he dropped a bolt in the motor.

Rebuild should be done by Monday... $2,200.

Thanks for the tip Mirge. I'm surprised you couldn't retrieve the bolt with a magnet. You must have been very unlucky and the bolt dropped thru an open valve into the combustion chamber.

Removing lower intake manifold

The photos below show the exposed lower intake manifold.


On the 2000 SOHC there is no vacuum reservoir to remove. Also, there are not two electrical components to remove as directed in mikeh's instructions. I chose to remove the PCV valve and its associated hoses. If you haven't replaced your PCV valve recently consider doing so while the upper intake manifold is removed. Access to 3 of the lower intake manifold mounting bolts on the driver side is restricted by the engine electrical harness. I decided to disconnect the main plug shown in the photo below.

I tied the harness and plug out of the way as shown below.

After that the only minor obstruction to the bolts are semi-rigid vacuum lines that can be nudged out of the way. After extracting all of the 12 bolts be careful when removing the manifold. There is very little clearance between the manifold and the fuel injectors.

It appers to me that the manifold is not keyed and can be installed rotated 180 degrees from the original position. I could not find any front marking so I suggest that you add one prior to removal.

Inspection of EGR seal & lower intake manifold

The photo below is a closeup of the EGR tube. The O ring seal is identifed with the red arrow.

This is another possible source of vacuum leak that I have not seen discussed in any previous post. The O ring was in good condition with no breaks. This is what binds the upper intake manifold during its removal and can be torn if care is not used. I decided that it was still useable so I applied vinyl/rubber conditioner to it to soften it for a better seal. I would not attempt to remove the O ring unless you plan to replace it. I suspect it is brittle and will break if you try to remove it.

I inspected the lower intake manifold for cracks and was pleased that I found none. The bottom of the manifold is shown in the photo below. The extensive carbon buildup is obvious.

Note that one bushing on the upper middle port is slot keyed and one on the lower is smaller in diameter. There are no corresponding keys on the heads. On my Sport, the slot bushing goes on the driver side. None of the lower O rings were cracked or broken but after almost a decade of being compressed they no longer rose above the adjacent surface. The photos below show the head intake ports after removal of the lower intake manifold.

The nonuniformity of buildup around each port is an indication of leakage.

I sprayed throttle body cleaner down each port to soften the carbon buildup prior to stuffing shop towels into each port to keep things from falling in.

I strongly suggest spraying the location where the tensioner hex nut contacts the casting with penetrating solvent several hours prior to attempting removal.

After plugging all of the intake ports with shop towels I used my leaf blower to blow out all of the loose accumulation on top of the heads.

Ford Genuine Parts

The photo below shows the 00M12 kit as received and unpacked. There were no instructions other than to use all of the parts included. On the box is the statement "CONTENTS MADE IN ITALY ALL OTHER COMPONENTS OF U.S. ORIGIN". So at least the box was made in the United States! I was a little concerned that the gaskets were stuffed in the box loose with the chain tensioner but they seemed to be in good condition.

There are 6 single ring gaskets for the bottom of the lower intake manifold (where the leaks are) and 2 triple ring gaskets for the top of the manifold. There is also a new front upper chain tensioner and washer. The long plastic rod is simply an oil gallery volume reducer. And there is its associated access plug.

I want to point out that I am not optimistic about the new chain tensioner curing all of my chain rattle problems. I suspect that my chain guides are significantly worn and that they will eventually have to be replaced. However, I am following the Ford advised progression process for chain rattle resolution and avoiding the cost and expense of each step as long as possible. Eventually my engine will have to be rebuilt or replaced and I prefer to resolve the chain guide issue at that time if possible. It is my opinion that the excessive guide wear is mainly due to defective oil lubrication design and can be prevented with a preoiler. I will install a preoiler prior to my engine rebuild.

IAC valve base

The photo below is a close up of the bottom of the base that the IAC valve mounts on after I removed it from the upper intake manifold.

The red arrows identify the thin gasket that fits in a narrow slot around the perimeter of the base. If the gasket does not seal then air will leak into the chamber below the IAC valve. Fortunately my gasket was in good condition but I will apply vinyl/rubber conditioner to soften it before reassembly. It is also important that the 4 torx screws holding the base are snug. The blue arrow identifies the vent that allows IAC valve controlled air to enter the upper intake manifold. If this vent is blocked with buildup then the IAC valve won't work properly. Mine was much cleaner than the rest of the intake manifold further supporting my claim that most of the carbon buildup comes from the EGR pipe. The green arrow identifies the IAC valve inlet port. There is a short hose that connects the rigid tube from the main air intake to the inlet port that can crack and leak air. My hose had no cracks but was fairly loose so I will add a hose clamp upon reassembly.

Removing tensioner & galley plug

CAUTION The ECT sensor and the engine temperature sending unit screw into brass fittings poorly mounted in the plastic thermostat housing. The fittings can spin in the housing and then leak. The thermostat housing is very expensive to replace (>$300). Avoid removing either sensor. If you must remove one, be very careful!

The photo below shows the rusty tensioner after removal of the ECT sensor. mikeh removed his tensioner with a 1 1/16 inch wrench.

The only wrench I have that large is an adjustable and there isn't room nor would I use it if there were. I decided to use a deep well socket but in order to do that I also had to remove the engine temperature sending unit for the instrument panel next to the ECT sensor. The photo below shows the sending unit with the electrical connector disconnected.

The two sensors are similar in size and shape but not the same part. The threads are different so I made sure to keep track of which one went where. I should point out that if you've had any trouble with either sensor this is an excellent time to replace it. Replacing either sensor requires removal of the upper intake manifold. I used a 19mm deep well socket to remove each sensor. There are washer seals for each sensor that were stuck to the top of the thermostat housing. The photo below shows a 27mm deep well socket in place over the tensioner connected to a half inch torque wrench.

Even though the tensioner head had soaked in Blaster for at least an hour, about 75 ft-lbs was still required to loosen it. I was concerned that any more than that might break the casting. The photo below shows a #30 torx bit inserted into the gallery plug and connected to a 1/4 inch drive.

The fuel injection wiring harness and fuel lines are in the way but I was able to work around them. I was extremely careful not to drop the gallery plug and socket.

Installation & results

CAUTION: McSlug has provided an excellent tip regarding the installation of the new tensioner. It is very important to ensure the compression ring on the tensioner is centered when the hex head face contacts the head. If the compression ring is not centered then oil will leak profusely no matter how tight the tensioner. Applying a small amount of gasket sealer between the compression ring and the tensioner face will keep the ring in the correct position.

The installation was according to mikeh's instructions with the following exceptions and additions:

When installing the lower intake manifold that has no guide pins, look thru the manifold runners to center them with the cylinder ports.

Torque the lower intake manifold bolts starting at the center and working outward at opposite sides. Torque the bolt set in steps: 60, 90, 110, 120 in-lbs. The specified torque is 107-123 in-lbs.

No vacuum reservoir or rail to install on my 2000 Sport.

If you disconnected the rigid tube with hose connecter from the IAC valve base for any reason it must be reconnected prior to installing the upper intake manifold.

Torque the upper intake manifold screws starting at the center and working outward. Torque the screw set in steps: 20, 35, 50, 60 in-lbs. The specified torque is 53-62 in-lbs.

My engine started immediately after not being run for 5 days. The start up rpm flare was significantly reduced. The chain rattle was loud for a very brief period until the oil got to it. I had compared the strength of the old and new tensioners and the new one was not much stronger. Consequently, I did not expect a significant change in the chain rattle which is probably due to worn chain guides. The second start up was much quieter so the installation of the oil drain restrictor was worth the cost and effort. The engine idles smoother for various engine coolant temperatures and its good to know that now less of the air that enters the engine has bypassed the air filter and MAF sensor. I plan to add hose clamps to some of the vacuum lines to tighten their connection.

I spent several hours cleaning the carbon from the upper and lower intake manifolds and head intake ports. I had sprayed them with throttle body cleaner several times over a 3 day period but much scraping was still required. I just don't see how adding Sea Foam to the intake will signficantly reduce the carbon buildup during the brief time it is in contact with the carbon while the engine is running.

Nice write up, thinking of doing this to my 00 every first start of the day it sounds like its bout to lockup or something with that loud rattle at first plus like you mentioned the way it idles at first. So that is the tensioner that usually needs replacing? I'd like to know what parts to order before actually tearing into the motor, thanks

Ford changed the intake slightly, deleting the vacuum reservoir, and the variable intake valve.

The chain guides more commonly break as opposed to wearing down. The tensioners should be doing their job, pushing the guides against the chain.

At 187k+ miles my guides had 1/6"-3/32" of wear on them. They just disintegrated and went all through the engine.

I seen the parts number at the beginning, I was merely asking if that is the normal tensioner that goes bad, that I shouldn't have to order any other parts except for the one you listed I read through your thread I wasn't asking for any part numbers so I don't need bold print.

1st phase

I believe the Ford suggested progression for chain trouble repair is to first replace the tensioner for the upper front chain. If there is still chain noise in that area then the cassette should be replaced which involves removing the valve cover. The tensioner and oil restrictor included in the 00M12 kit is a possible inexpensive and quick fix to try. My next step is to use a mechanic's stethoscope to listen for chain rattle coming from the upper front of the engine. There is another cassette/tensioner in the middle front for the chain that connects the crankshaft and the jackshaft. A third cassette/tensioner is located under the passenger side valve cover in the extreme rear. There's an excellent set of photos near the bottom of the first page of this thread.

Alright thanks for the info, I'll have to buy this kit and see if it cures the rattle.

Not trying to up a dead thread or anything, maybe you know. From pictures I can tell the motor in your 2000 is similar do you know how much of a difference there is between my 98SOHC. Ie could I use this as a guide when I do mine in a few weeks when it warms up.

Sohc vis

If your 1998 has the SOHC then about the only significant difference from the 2000 SOHC is the variable induction system (VIS) that was used in 1997 and 1998. There is a vacuum motor near the top and rear of the engine with a rod that controls variable intake runners. The thread I reference in my thread was based on a 1998 SOHC. Use it as your primary reference and mine as a supplement.

Join the Elite Explorers for $20 each year.
Elite Explorer members see no advertisements, no banner ads, no double underlined links,.
Add an avatar, upload photo attachments, and more!

Wow, didn't even see that link. Thanks.