Next project vehicle?

EGR system design (continued)

Below is the electrical diagram for the Aviator EGR system.


.cnx .. Pin Wire color . Signal name
PCM Relay Red/Yel ...... Power
C175E 16 Brn/Pnk ..... EVR Ctrl
C175E 17 Gry/Red ..... Return
C175E 20 Brn/Wht .... V Ref
C175E 41 Brn/Lt Grn . DFPE Sense
C175E 59 Lt Grn/Blk .. Map Sig

The 2002 Explorer diagram is very similar.


..cnx.. Pin Wire color .... Signal name
BJB Fuse Red/Yel ...... Power
C175C 16 Brn/Pnk ..... EVR Ctrl
C175C 17 Gry/Red ..... Return
C175C 20 Brn/Wht .... V Ref
C175C 41 Brn/Lt Grn . DFPE Sense

It certainly would be convenient if the five signals from the Aviator EGR system module that are common with the Explorer EGR system signals were identical or very similar.

The 1998 MK VIII EGR system signal names are identical to the 2002.


However, the PCM connections are different.

Pin Wire color... Signal name
71 Red ........... Power
47 Brn/Pnk ..... EVR Ctrl
91 Gry/Red .... Return
90 Brn/Wht .... V Ref
65 Brn/Lt Grn . DFPE Sense

This is the aviator wiring for the ESM system.



This is the reference values for aviator



And these are for the 2003 explorer

column titles?

That data looks encouraging but I'm having trouble deciphering it.
The first column looks like PIDs available from the PCM via the OBD-II port.
The second column looks like test numbers. I assume "E" refers to emissions.
The next 4 columns look like acceptable limits. Can you provide the column titles?
The last column is the units for the acceptable values.
It's encouraging that the DPFEGR PID values for the Aviator are identical to those for the Explorer.
I was puzzled by the MAP SIG I saw in the wiring diagram. I'm guessing that the EGR system module contains a sensor for the vacuum connection from the internal EVR to the EGR valve. That would increase fault detection and isolation capabilities. If I'm correct then the four value columns are probably for different engine loads such as not running, idle, cruise and WOT. I don't know the order though. EGR is disabled at WOT and idle so one pair of columns should be associated with those conditions.

I should be able to monitor/datalog the DFEGR PID on my Sport to determine what values are typical for various engine loads.

Edit: I just noticed that the LOAD PID is listed for the Explorer table and it increases for each column: (L), 16-23%, 20%, 25% and the throttle position sensor voltage (TPV) is listed: .53-1.27, .53-1.27, 1.3-1.5, 1.5-1.8. The first two columns are probably for closed throttle.

Sorry about that, I am just used to looking at this and forgot other people don't use ford manuals every day. This should help.

workshop manuals?

Are those tests in these workshop manuals or are you using dealer only manuals?

I haven't found a CD/DVD shop manual online yet and I need the engine assembly/disassembly instructions. The above are available for $50 plus $10 for shipping. Maybe I should buy them.

No, they are in the black PC/ED manual. The workshop manual covers everything except drivability related items, which is all in the PC/ED. It is not vehicle specific, there is only 1 manual each year and all models are put in that manual, since most of them have are identical as far as drivability is concerned. I have access to it online, which is where I got those pics. I can get you whatever you need, but I can't give you access. The manuals in that picture are what we have at the dealership. I haven't used them in years, I only use the online versions. I can print it off if I need it also.

As far as if you should buy those, the workshop manual will cover everything you need to assemble the engine, and the wiring book will help also.

Engine wiring harness & throttle body?

That explains why I've never seen those tests before. I purchased the manuals.

You mentioned in your thread that your engine wiring harness is made up from the Explorer and a Navigator wiring harness. I'll know more about the wiring when I get the Aviator manuals and purchase Explorer manuals or CD. I'm wondering if it would be easier to start with an Aviator wiring harness. The salvage yard I went to didn't have one but I can get one from Florida for around $150.

The throttle body assembly that came with my engine has a round intake with a single throttle plate (instead of an oval intake with dual throttle plates) and an EVR. I suspect it came off the donor engine for the Aviator. I found a drawing online that resembles my throttle body assembly configuration.

The drawing number is P-31294 and the date is 3/22/2005. I'm wondering if the early Aviators had a separate component EGR system and Ford later upgraded to the integrated EGR system module. I haven't test fit the intake manifold I got with the block/heads or the throttle body with the intake manifold. Hopefully they'll fit together and the throttle body intake will face the passenger side. I measured the throttle body intake port to be 68 mm which is smaller than the 75 mm one I installed on my Sport. I'll probably upgrade when I install a supercharger.

I had to reorganize my garage to make room for two vehicles, my little trailer standing on end, the crane, engine stand and engine. The bolts I used to mount my SOHC V6 block to the stand were the same thread as the DOHC V8 block but some of the block threads needed chasing. I purchased a metric tap and die set and thread cutting oil aerosol from Harbor Freight to chase the threads but the set was a piece of junk. The thread depth on the tap was small so the bore of the tap was excessive so I didn't use it. I was able to chase the threads with cutting oil using my quality bolts and brushes and got the block mounted yesterday. It's so much wider than my V6. Today I'll check to see if there is an oil pump pickup tube and windage tray.

That drawing is weird, the throttle body is facing the wrong direction. The aviators always had it pointing to the passenger side. When I was first looking into this swap, I found a guy who milled the throttle body mount off the top of the upper intake and mated a dual bore throttle body from another intake to it. I'll see if I can find it.

Aluminum intake, plenum & throttle body

I found an Aviator aluminum intake, plenum & throttle body posted on eBay:

It looks like I have something similar to what's on top.

But what I have below is one large plastic casting.



Edit: I think I found a photo of what I have. Its a 1999 Mustang GT intake manifold so I doubt it will fit my heads.

Yes, that is a 2v 4.6 intake. It definitely won't fit. The intake ports are way different, and the 2v intake is wider. Since you have "c" port heads, you can run a 1999-2002 cobra intake and you won't have to modify anything. Plus they only run about $250 - $450 on eBay, and they are already dual bore throttle body. Or a Mach 1 intake. I don't think they all have the variable runners, but some do. You will also be able to put a 2003-2004 cobra supercharger and intercooler setup on. I so wish I had waited and found a "c" headed engine. I guess I can always upgrade later.

cost considerations

Since I have the tumble port heads I need a 1999 or later intake system. It seems the later the year the greater the cost. I'll need to purchase an intake manifold, plenum, throttle body and injectors. If I eventually install a supercharger (remember I don't want an Eaton) then I'll need to replace the intake manifold, plenum, injectors and possibly the throttle body. Therefore, from a cost perspective I should spend as little as possible now for those items. There's an entire Aviator intake system (fuel rails??) listed on ebay for $350 with free shipping: 03 04 05 LINCOLN AVIATOR 4.6L DOHC INTAKE MANIFOLD
What do you think?

Mach 1 intake

After further research I've decided to watch for a Mach 1 intake system. The Aviator max horsepower at the flywheel is 302 while the Mach 1 and Cobra is rated at 305. Since the rest of the engine is basically the same I'm assuming the extra 3 bhp is due to the intake system. My budgetary planning for my Sport improvements was $100/rwhp increase. So I guess the Mach 1 intake system is worth the extra money but not the Cobra. I suspect the reason the Cobra intake is more expensive is because of the logo on the plenum and the status associated with it. It appears the Kenne Bell blower kit mates with either the Mach 1 or Cobra throttle body but not the Aviator.

From the wiring diagrams it appears that the Mach 1 intake manifold doesn't have IMRC which will match the capabilities of the Explorer PCM simplifying things a little. Also, the Mach 1 has the individual component EGR system instead of the integrated EGR system module.

Fuel rails

The Mach 1 fuel rails have a mounted fuel pressure sensor. The Aviator fuel rails have the same fuel pressure sensor but also a fuel pressure damper on each side of the rail for each bank. When I installed custom fuel rails on my Sport I replaced the stock fuel pressure damper with a fuel pressure sensor. The fuel pressure gauge measured significant pressure spikes when the injectors fired. I built a damper using brass fittings and a tube to reduce the spikes.


To avoid a similar problem I'll try to find Aviator fuel rails. Hopefully, they'll fit the Mach 1 intake manifold.

A supercharged, bored and stroked, DOHC 4.6L may require a higher flow fuel pump than the stock one for the NA, 2 valve 4.6L Explorer. When I installed my Stealth 340 high flow fuel pump on my Sport I found that for normal driving most of the fuel from the pump immediately returns to the tank via the intank fuel pressure regulator. So I installed a fuel pressure sensor on the custom fuel rails and an electronic fuel pump controller to keep the pressure at the rails fairly constant at the desired setting. The fuel pressure sensor on the stock Aviator fuel rails will simplify fuel pump control. Explorers did not have fuel pump control until around 2004.

The 2002-2003 explorers utilize a mechanical return less fuel system, the aviators have electronic returnless systems. When the explorer switched to fly by wire in 2004, the other fuel system was added. In the early explorers there are 2 lines into the fuel filter and one out to the engine. The filter is held at line pressure along with the line to the engine. The return line comes out of the filter and goes back to the tank and the internal pressure regulator. They run a higher static pressure than a normal return system, at 40-65 psi. Standard systems with return lines usually run 30-45 psi. The aviator electronic system varies the fuel pump speed to control fuel pressure based on info from the rail pressure sensor.

There is a Mach 1 intake on eBay for $325 right now. It is complete minus the fuel rail. It isn't a buy it now however.

Mach 1 intake

It was a "buy it now" for $450 until I bid the minimum of $325. How high should I go?

I don't know maybe $375?

Oval inlet tube?

I've been searching for an inlet tube that will mate with the oval Mach 1 throttle body on one end and have a round port on the other end to mate with a MAF sensor. The Lightning 90 mm MAF sensor should be good to 500 hp, is fairly cheap, and I have bench flow test data for it for tuning. It has a 4 inch dia. outlet. I can use two couplers and a reducer to get to other diameters but I need something to mate with the throttle body. The short section of the Mach 1 looks promising since I know that it fits the throttle body.


I assume that the MAF sensor is in the air filter housing. From what I've read so far on the Mach1 Registry the stock MAF sensor is the integrated type with the IAT sensor and the MAF sensor in the same housing and is smaller in diameter than the 90 mm MAF sensor but I can't seem to find the size.

The maf bolts to the back of the housing in those 4 lugs sticking out. The only thing inside the housing is a conical filter.why don't you just look for a lightning intake tube. They have an oval throttle body and you know they fit the maf.

Lightning intake tube

I didn't even consider the Lightning because the air filter is on the driver side and I want to use the stock explorer filter on the passenger side. However, after looking at one it does have possibilities if I flip it over. Thanks for the suggestion!

It looks like there are three ports. The large ones are probably for the IAC valve and PCV crankcase ventilation. I don't know what the small one is for - possibly to a MAP sensor? I'll spend some time researching the Lightning.