P0401 Check Engine Code/ Burning Oil

The code talks about your egr system. Probably, its ditty, and needs to be cleaned out!

There lots of videos on YouTube on the procedures involved. Just type EGR cleaning procedures, and everything cones out.

 

Welcome to Prius Chat .

Some questions:

• How many miles on your Prius?
• Have you cleaned the egr circuit before?
• How much oil is your Prius consuming and in what period of miles?
• Are you the DIY type?

Search around in the Gen3 maintenance section and you’ll find some videos on removing, cleaning and replacing the whole egr circuit in the @NutzAboutBolts thread pinned there.

With what you are reporting, your egr circuit is most likely clogged and if not dealt with soon, you may lose your head gasket.

Good luck and keep us posted .

 

Ours had 212k and the cooler was totally blocked. When the flow falls or the valve sticks you get the code. It's easier to take the valve and cooler off together vs just the valve. Not knowing the condition of ours I ordered a new valve ... thinking we could clean the cooler.. On initial removal it was clear that the intake was also clogged ..and would need to be removed.

My cooler was so clogged -- we could not clean it. Even soaking over the weekend in solvent did not free it up ... had already ordered another anyway. So... mine got a new valve and cooler. We were able to clean the pipe to the intake and the intake itself (and the 4 small ports)

The EGR works by taking some of the exhaust gas and injecting it into the intake -- to do this it has to first cool that hot exhaust. It does this by way of a "cooler" connected to the exhaust system .. The gas goes through this and is cooled by the coolant of the engine (yes it's got water connections) this now cooler exhaust gas is allowed to flow to the intake through the EGR valve -- the valve has a plunger controlled by the cars computer -- the valve modulates the flow. The gases flow from the valve by way of a metal tube to the plastic intake.

Unfortunately -- there is a lot of soot in this exhaust ... the soot clogs the cooler/ valve/ metal tube and the intake. Some report cleaning the valve -- I was not going to take that chance because of the labor involved. You will not know if successful until all back together.

The valve is about $200 and the cooler is $275 ... online dealer .. not local dealer pricing. It was too much work for me and my time line ... as it was --- it took a few days and the cooler delay. I have been spraying the cooler for another few days and it's still clogged.

Not a cheap fix. There are used coolers available on e-bay ... the question is how clogged. My plan is to try and clean the one I have eventually -- as we have other Prius / Lexus with the same setup.

This was done on mine last week

Also: note when you plugs were last done. it's easy to do while you are in there and the latest plug is slightly hotter vs original. If the intake comes off -- replace the PVC valve. it's right there and easy to do -- cheap. It's a pain otherwise.

 

With that mileage and a severe oil consumption issue, you’ll need to look into doing the egr circuit sooner rather than later.

While te P0401 code has displayed, it is indicative of a dirty egr circuit. If not gotten to soon, the head gasket might get compromised.

Look on the Gen3 maintenance section and pinned at the top of the forum is a thread of maintenance videos done by @NutzAboutBolts . They’ll show you how to clean the egr circuit from cooler through the intake manifold .

They show the tools you’ll need, but an E8 Torx socket comes in handy along with ratcheting wrenches .

Good luck and keep us posted .

 

At 212k we were not using anywhere near that much oil. Maybe a quart in 2500 miles ....

I would not call the job "hard" .. but it is involved. And it does require pinching off the coolant lines to the cooler ..or you will have coolant all over the place. There are gaskets involved in all the connections.

The issue you will not know: how dirty the parts . If not able to clean you will then need to source parts. Also -- it's very hard to determine the success rate with cleaning the EGR once there is a problem. People doing the full cleaning at 80k as a hopeful preemptive move with a working EGR is not the same as someone trying to fix a malfunctioning valve.

As I said above: if your cooler is clogged like mine .. you may not be able to get it clean in a timely fashion. Maybe try and get good used on e-bay or junk yard. You don't want to get it all back together and find out the valve is bad and have to take it all apart again.

My guess is you will need to remove the intake as well -- using a mirror to look into the opening (after the tube is removed) you will see the soot. Had we just installed the new valve and cooler -- the problem would not have been fixed. The gasses from the valve have to get through the passageways of the intake -- they are very small at each cylinder bank.

 

If you pinch off the hoses on the EGR cooler, then pull them off, you will still have a deluge of coolant: many of the hoses are level with or below the coolant filled cooler.

A simpler method: drain a couple of liters into a clean container(at the radiator drain spigot) before pulling any hoses off. Then, when removing the cooler there's no coolant in the lines, and only a little residual cooler at the lower back corner of the cooler. Lift the cooler out without tipping it, and pour that residual into the container you used to drain the other two liters.

After everything's reinstalled, leave the coolant vent valve (2010, 2011 model years) open, or leave topmost coolant hose loose (2012 onward, which don't have the vent), and pour the coolant back into the reservoir, while periodically "burping" some of the bigger coolant hoses. Close the coolant vent (or reinstall loose hose) once coolant reaches it.

 

Mendel -- not sure what your refer ? My independent used the hose pinch clamps -- nothing came out except what was in the cooler .. and that would have been there anyway. There was tiny amount. I had a new gallon ... so they just topped off the tank when finished.

I had done the coolant refresh last fall. Obviously, if in need of coolant refresh this the time to drain

 

Guys if anyone wants a cheap egr cooler, I got one for sale for $50. I don't have time to clean it. Also have all the other egr parts for sale.

 

I would think there's about 2 cups in the cooler, plus the lengths of hose beyond the clamps. Preemptively draining 2 liters at the bottom drops the level below the EGR system, it's effectively dry when you come to remove it. Very easy.

EGR & Intake Manifold Clean Results | Page 3 | PriusChat

 

I can use the cooler; I have a 2012 v wagon approaching 100k miles and want to get ahead of this oil burning, head gasket issue. Also bought an OCC to be installed at the same time. What other EGR parts do you have?

 

Which year? I’m very interested and can PayPal you funds to cover for shipping also. I need to do the EGR cleaning during the winter, ain’t gonna do it during hot summer.

 

I was questioning your idea that one would get a deluge of coolant if you pinch off the lines w/o draining the system -- no extra coolant comes out.

 

I've got the valve and the pipe. Selling cheap!

 

It's a 2010. The cooler is filled with carbon but with the copper wire and drill method it would be pretty easy to clean from what I've read. I've got the valve pretty clean, and the pipe. Selling them cheap. Need them gone. Let me know!

 

I can use them all; intend to do the service this fall when it's cooler but ready for the parts now to get them cleaned up.

 

Yes it does, the egr is clogged that causes the engine has to work harder. The harder engine works the more oil burns.

 

Send me a PM