Finding the EGR valve caked with soot is very common. The soot should be dry packed powder. If it is greasy feeling, it is likely that the egr cooler has failed due to a plugged oil cooler (on the coolant side of it).
Test it out by parking the truck on a decline, pull the egr valve out of the intake, leave it like this overnight. In the meantime, CLICK HERE
to learn how to clean the valve while you have it out.
In the morning, check the bottom of the hole that the valve sits in. If you find any evidence of moisture, the egr cooler has failed.
What causes this is the coolant. If the coolant was not properly checked and maintained, the coolant will create a gunk that gets caught in the coolant passages of the oil cooler. This will slow the coolant flow and will result in hotter oil temps. The coolant that exits the oil cooler is directly fed to the egr cooler. The slower moving coolant fed to the egr cooler allows the egr cooler to overheat and fail internally. At that point you have coolant leakingout of the egr cooler. The coolant goes one of two directions depending on what the PCM is commanding the egr valve to do.
When the valve is closed, coolant is flowing into the exhaust and is pushed through the side of the turbo that has the vanes in it to control boost. Soot, coolant and heat make a nice muck in there and interfere with the operation of those vanes. Overboost and underboost may occur at any time. When the truck is turned off, the coolant continues to leak out of the failure in the egr cooler. The coolant will flow down the up-pipe on the passenger side of the engine, and down into the exhaust manifold. Should the failure point be large enough, the coolant could flow enough to enter whatever cylinder happens to have the exhaust valves open. This would result in a hydrolocked condition.
When the PCM commands the egr valve open, your engine is taking a big gulp of coolant that built up behind the valve. This is what causes most head gasket failures on this engine.
What needs to be done is to verify that it is the egr cooler failure, then address the problem quickly, before much more expensive repairs are needed.
If the egr cooler has failed, you need to flush the cooling system so that your new oil cooler will not become clogged quickly with the junk that clogged the existing one.
The best flushing process is to use two separate chemicals in two separate flushes with a few flushes between each chemical and many flushes after to be sure you get all the junk out of there. BUT, running the engine down the road with a failed egr cooler can pop a head gasket.
There is only one way that I know of to do a flush while minimizing the chance of that happening. First, clean the egr valve and verify that the valve is fully closed and sealed. Use a vac and vac out any large chunks of soot that is in the hole in the intake when you remove the egr valve.
Next, to be able to run the engine higher than idle without driving the truck, you will need to do what is called the "high-idle mod," which is quite easy on an 07 truck.
To do that mod, find the cluster of dead-ended wires tucked up just above your emergency brake pedal. In that cluster, find a purple wire with a green stripe. Apply 12 volts to that wire (preferably with an inline 5 amp fuse). After you do this, set the emergency brake, have the truck in park and keep your feet of the regular brake, the engine will idle up to 1200 RPM. This should be high enough for an effective flush.
Next, when you replace the egr valve, do not plug it back in electronically. This will prevent the valve from opening while at idle speeds. It WILL NOT stop the valve from opening if you drive the truck. The pressures that the valve sees from the turbo while driving may force the valve open. Don't do it.
After all the above is done, drain all the coolant that you can by pulling the lower radiator hose off, and open the block drains. There are two drains, one on each side of the block. I believe they are 10mm allen heads. The passenger side is a pain in the rear to get out. Most people don't bother taking it out since you have to take the starter out to get to it.
After that is done, button it all back up, pour in 3-4 gallons of distilled water and run the engine up to normal operating temp (using the high idle).
Drain, button it back up.
Add 2 quarts of the Ford product VC-9, add distilled water until full.
Run the engine up to operating temps (on high idle). After it reaches operating temp, allow the engine to run about an hour.
Drain, fill with distilled, run up to temp, drain, fill with distilled, run to temp, drain.
Add second chemical (restore). Fill with distilled, after reaching operating temp, run for one hour.
Drain and flush the block as many times as it takes to get the water coming out of the block as clean as it is when you poured it in.
After the last drain, pour 3 1/2 gallons of CONCENTRATED coolant. Since the cooling system retains about 45-50% of total capacity even when the block drains are open, if you used a premix you could never reach the 50-50 mix.
It is strongly recommended that you do not use the Ford Gold coolant again.
NAPA sells a Zerex coolant that is CAT EC-1 rated and an ELC. Buy 4 gallons of the concentrated form of this coolant.
After filling the cooling system, run the truck for a bit to mix it all up with the existing distilled water in the block. Then use the radiator pet c o c k (damn censor will kick that word) to drain off what you can, then use a clean 5 gallon bucket and slide it under the lower radiator hose to collect the coolant. By doing this you have replaced the straight water that is in the block that could start rust forming in the cooling system. Just keep the coolant covered to be used after repairing the oil/egr cooler.
If you want/can, now is a great time to install an egr delete kit.
In my signature line, there is a link entitled "step by step..." that has alot of helpful notes/tips and the PDF files that you will need to do all of this repair yourself (including splitting the turbo to clean it). If you get stuck anywhere along the line, post up on this forum. There are alot of guys here that are knowledgeable and would be very happy to help.