EGR system cleanout

The valve actuator is nothing more than a six-terminal stepper motor whose rotor spins on the threaded valve pintle. It's pretty robust. If you open it up you'll see there's not much involved there.

Of course you want to avoid any kind of cleaning in that area that would strip the lube from the pintle threads or the two ball bearings of the rotor.

Opening it up is good anyway, to check the condition of the 'ski jump' rotation stop inside the rotor, which sometimes gets mashed.




The electronics for driving the thing are all in the ECM, not in the valve itself.

 

Yeah shelve the parts cannon, just clean everything. Gasket replacement is not mandatory. I did replace the intake manifold gaskets second time around (at 95K kms), but I think it was overkill.

For cleaning, what worked for me:

For the EGR cooler I corked one end end and filled with a concentrated solution of hot tap water and Oxi-Clean Versatile Cleaner (powdered laundry additive). Let sit about an hour, drain, rinse, repeat. About 5 sessions thus it was like new. To be fair, I got on the cleaning very early (around 70K kms), and followed up just recently (95K kms). With more entrenched carbon more mechanical methods, harsher caustics (oven cleaner, lye solution), and/or a pressure washer, may be needed. The cooler is 100% stainless steel, so immune to the somewhat corrosive properties of this cleaner.

For the EGR valve I used brake cleaner (a little more benign than "carb" cleaner) with rags and brushes, worked fine. Do be careful with the electronics, just deal with the carbon; don't spray indiscriminately.

For the EGR pipe I also used brake cleaner, brushes and rags. Being stainless steel, you could use Oxi, but it'd be overkill.

For the intake manifold, again just brake cleaner, brushes and rags. Oxi, being caustic, will be hard on its metal inserts.

First couple of links in my signature have more information.

What's the miles btw?

 

My mechanic wants to run 'SeaFoam' in one of the vacuum intakes to flush the EGR, once a year.

 

The Seafoam will have been magically converted into exhaust by the time it even reaches any of the EGR components.

 

You can do it with a 12 VDC supply and a couple of SPDT pushbuttons. Take a look at this post and this one.

 

I've never seen anything bad happen to the original white lube, other than some of it ending up in places where it isn't lubing anything. I just scoop it up from those places and put it back on the threads. Saves any worry about what's compatible with it.

It kind of looks like a garden-variety white lithium, but I prefer to just reuse it so I don't have to guess.

 

It's easier than that. Squeeze the tensioner plunger back in, and look for the little hook you can swing into place to hold it there. Reinsert the tensioner that way and bolt it down. Then apply a bit of reverse motion (counterclockwise, looking at the crankshaft end) to the crankshaft, which puts tension on the stretch of chain that's against the tensioner, and pushes it in so the hook drops away. Then turn the crankshaft back in the forward direction a bit, and you should hear the tensioner ratchet back out.

Have you got the valve cover off so you can see the timing marks on the cam sprockets?

Once you have the tensioner back in place and the hook released, you can gently, carefully turn the crankshaft forward until all the marks are aligned, and confirm everything stayed in time. But do this very gently and stop if you feel resistance.

You can take out the spark plugs so there's no compression. That way you won't be fooled by the force needed to turn the crank against compression. With the plugs out, you should be able to turn the crankshaft easily by hand; it shouldn't feel much different from a sewing machine.

The painted chain links will not be on their sprocket marks every time you see them. That's normal. They'll be on the proper marks every ninth time they go by. So if it doesn't look right the first time you see them, you could have to keep turning until they've come around as many as 8 more times worst case, about 4 times on average.

If they go by nine times and were never on the proper marks any of those times, your timing is off.