Still P0401 after cleaning egr !! should we drive it?

If relevant conditions change significantly while it's trying to perform that test, all they have to do is throw out the interrupted attempt and try again later. The reported minimum passing values don't vary much, do they? If they use a consistent throttle angle (or consistent initial manifold pressure), and consistent EGR valve opening during that test, no other relevant variable should vary much except atmospheric pressure. According to my ScanGauge, engine speed is always 992 RPM when the engine is spinning without injection, if wheel speed is close to constant.

 

The reported 'min' values don't vary by a whole lot. But what's weird, and in need of some explanation, is that they vary at all.

 

Another two sets of numbers:

2015 @ 73K that is still running great - no EGR service work done.
2015 - Catalyst Monitor Bank 1 - Min: 1, Max: 65.535, Current: 2.466
2015 - EGR Monitor Bank 1 - Min: 0.99kPa, Max: 655.35kPa, Current: 20.87kPa

2010 @ 253K that had its last EGR cleaning in Feb 2018 @ 234K.
2010 - Catalyst Monitor Bank 1 - Min: 0.055, Max: 9.994, Current: 0.16
2010 - EGR Monitor Bank 1 - Min: 0.99kPa, Max: 655.35kPa, Current: 14.6kPa


2015 @ 73K


2010 @ 253K

 

Hello everyone. I have the same problem with the p0401 code after cleaning the EGR valve with the cooler and intake. So I decided to buy a used EGR from a Toyota Urban cruise 1.3 it cost about $12

so I decided to take it apart and compare, they both looked the same.

From the left is urban cruiser right prius.
Before changing Tis reading:

After changing and clearing the error and a short drive, the code did not come back and in Tis I have this reading:
so I think it should be ok?, it's time to sleep. Goodbye

 

Hi!
You have not shown us the part number of the "new" valve.
I think it is a different number - our valve has no cooling pipes on it, right?

It can still be the equivalent part, but there is no guarantee, that, for example, the valve diameter is the same...

Your flow value after changing the valve is relatively low.
With the right valve and the EGR cooler and intake manifold clean, the value should be around 20.

After all - the rotor of the "new" valve looks OK.
Your old rotor looks damaged.

You could eventually change the rotor only (if it fits) - then you have your original valve with an intact rotor.

Mat

 

You are right, I forgot to write here the part number from Toyota Urban 25620-47020, and I only changed the magnetic part, it fit without any problem, now I am going on a trip for the weekend, so I think that 14 kpa is better than 0. After the weekend, I will measure the magnetic part with a caliper to verify it is identical.

 

14 kPa is _much_ better than zero
It is possible, that after your trip you will measure more than 14 - the measurements are not always the same, so fingers crossed!

I think, there is a very good chance, the rotor _is_ the same.
I can hardly imagine, that Toyota developed it differently
If it fits inside the stator and apparently it does open the valve - it should be OK.

You can eventually double-check the dimensions and, more important, the count of poles in the rotor. You can not see it, but you can easily check it with a small magnet or simply a small piece of magnetic steel. Compare it with the old rotor.

Good luck!

Mat

P.S. Was your EGR cooler clogged completely?

 

Yes, and what was the miles?

 

I'm sorry I'm replying so late, but I had more important things to do. Yes, it was completely clogged, the car has 250,000 km, something like 155 miles, the next measurement was almost 19 kpa it's OK for me.

 

Thank you for the information!
19 kPa is ones again much better than 14 kPa, and even better than mine (not yet cleaned) at about 110 000 km
I would read the value, say, once a month? To see how it behaves. It is possible, that it climbs even higher.
But 19 kPa is absolutely OK, I would say.

Mat

PS. Poland? Are you kidding me??