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Lincoln Aviator 4.6 swap into 99GT

You also might try testing the fuel pressure. If the regulator is fragged it could raise the system pressure and run pig rich.

Saw it on a turbo vrod once. Barely ran, and when it did it left a trail of black smoke. Diaphragm in the adjustable regulator split and system pressure was over 200 psi. Kind of scary when I think back on it.

I would expect a dead or dying coil to throw a code...

A decent handheld scanner would make short work of any issues with sensors, as you can see them as they are being operated. Full sweep of TPS, ECT sensor from cold to warm, etc.

Another thing that comes to mind is whether the coolant temperature sensor is working as it should. If the car thinks it's 40 below and it's warm out it'll be dumping a lot more fuel in than it should be.
 
The problem with the scanner (which we did buy) is the battery was stone dead when we bought it. Putting a new battery in reset the computer. We can't get it to run long enough to throw any codes. It also won't idle so we can't get some of the readings.
We can't test fuel pressure. It's a returnless system and it doesn't have a schrader valve in the fuel rail. That's why I tested by pulling the rails and putting the injectors in. If it had way too high pressure, the injectors might have leaked but they didn't.
Since we can't let it "warm up" there is no way to know if the coolant temp sensor is a problem. Also since it won't really start and run so it should be in a default mode ignoring things like the coolant temp and O2 sensors. The noid light confirmed the injectors are pulsing which is a good sign the PCM is telling them to pulse rather than full on. The system has a module to control the fuel pump. It doesn't run all the time. The pump pulses also based on the fuel rail pressure sensor input. The fuel rail pressure sensor has a vacuum line to the manifold and adjusts pressure based on manifold air pressure (MAP). They happen to be the same on the 99GT and the Aviator so we swapped them. Didn't fix the Aviator or hurt the GT so I think fuel pressure is okay. The noid light confirmed throttle position sensor was working. We did unplug the cam position sensor. That puts the ignition in default and sparks every time piston is at top dead center based on the crank trigger. That had no effect.
We did have it running a few seconds once after we cleared all the fuel out of the cylinders and it ran rich but was not misfiring. It actually sounded pretty good. It just keeps flooding itself with fuel. So far everything we have checked is okay.
I'm starting to see why we got it so cheap!
 
also I bought a compression tester today. It wouldn't fit down in the DOHC hole for the plugs. I took it back and got a better one with a adapter for such engines but it's cold and dark outside and my son is at work so I am not messing with it tonight!
 
Unless I'm looking wrong you can get a set of 8 msd coils for 140 ish on ebay.
I am very Leary of MSD parts at a fraction of OEM prices. I am gonna guess those are Chinese knock-off parts and not really MSD. My son's store carry's Accel brand but they are about $250 for a set of 8.
 
Could have an O2 sensor stuck lean which would cause a rich condition. Have you verified that you don't have a plugged cat? MAF can cause very similar conditions, will the mustang MAF work? Did you try a spark tester on the coils to see if they are all hitting?
 
Could have an O2 sensor stuck lean which would cause a rich condition. Have you verified that you don't have a plugged cat? MAF can cause very similar conditions, will the mustang MAF work? Did you try a spark tester on the coils to see if they are all hitting?
hmm, plugged cat? could be... how to test that?
I didn't use a spark tester but the screw driver in the plug boot worked. Just don't know if it's a strong spark.

Have you verified that the fuel is good?
bad gas, also a hmmm, could be. We can try to dump it.
 
So I was able to do a compression test today. No compression on all four driver's side cylinders. I thought to my self, probably not a head gasket. It was ZERO pressure on all four.
So I thought, maybe broken timing chain/bent valves. So I pulled the driver's side valve cover. All eight rocker arms for the top cam (intake) were laying in the bottom of the head. The others are firmly in place. Now explain to me how that happens?
IMG_6961.jpg IMG_6962.jpg
 
Wow. Was not expecting that at all.

At first guess, timing jumped a few teeth, retarding the intake cam to the point where all four intake valves bashed the top of the Pistons, bending the valves (no compression) and bashing the rockers off their mounts.

Rough...
 
Upon looking at this again and trying not to sound like too much of an idiot, more like all 8 valves kissed the pistons and hung open allowing the rockers to fall out...
 
yeah, I believe all 8 intake valves are bent.
My theory is it probably jumped a tooth on the previous owner. Which is why it quit running.
We had it running really briefly but also wouldn't run below about 1500 rpm and not smoothly. I think it jumped another fatal tooth or two on us. We never could get it to run again.
My son rotated the engine so the lobes were up on one cylinder and put the rockers back in. They went in easy so my guess was the valves were not closed all the way (bent).
We checked compression, still zero. Confirming bent.
so we are just going to pull it and rebuild it and part-out/scrap the rest of the SUV. He was going to rebuild it anyway before putting it the Mustang. We were just hoping to hear it run. But at least we know what's wrong. He wants to supercharge it so he was going to put the forged internals. The only added expense will be 8 valves.
 
So we have decided to still get the Aviator running. We are going to pull the head and check the pistons. If they are not destroyed we will replace the valves and the timing chains, slack adjusters, etc. and put this pig back together. My son will drive this thing during the winter. We will disassemble the 99GT and get it ready for the swap. in the spring we will pull the 4V and rebuild it. My son has been collecting the parts for the sawp. He has a Mach 1 hood and NOS Ford Mach 1 Shaker stuff still in the boxes.
We started Aviator disassembly
IMG_6975.jpg
 
I really need a bigger garage! The Aviator is in one bay, and the Bobcat is back in for service. It has an oil leak so my younger son is tearing into it.
IMG_6978.jpg IMG_6979.jpg
 
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