Not just another p0401.. PICS!

what you don't understand is that different fuels and/or additives can change the burn pattern and have impact on soot/carbon deposits formation. i was able to do a simple DIY demonstration on this some time ago. i can link my youtube videos later today.

 

Yeah please do.

I'm sceptical though, thinking the car's computers are going to determine the air/fuel ratio, the problem's not gonna go away, regardless of the gas. The Chevron I'm using has all the accolades, supposedly "top tier", whatever the reality of that is.

 

It's not my intent to just ignore it when the check engine light goes on. I just don't want to do extra maintenance at 100,000 miles when I change the cooling fluid. If it's drivable without hurting anything, I can get the parts and install within a week or two. I'm just trying to find out if a blocked EGR can cause damage to the engine if it's driven for a few days until parts are delivered.

I know what the answer probably is; I'm just seeing what others think.

 

I looked up hose clamps, they run $16~20. There's four lines running into the contraption, so if you were to clamp them all with kosher tools you're closing in on $100, with tax. And it would start to look like open heart surgery, a forest of clamps: with the tight space maybe not even doable. Guess this is best addressed in conjunction with an engine coolant change.

If Toyota had run a longer pipe up from the exhaust manifold, made that radiator contraption more accessible, and made the case in two halves with a gasket and screws, so you could open it up, clean the radiator. But no.

 

here you go:

besides, there are commercial cleaners that work some to clean EGR as shown here:

 

It just so happens I have been using Lucas UCL for years to keep the fuel injectors clean. After spending $600 on injectors for a Ford Van I've never had that problem again in any car since using Lucas.

I buy it by the gallon. About 3 oz. per 10 gallons of fuel. I'm driving about 20,000 miles/year. I have 50,000 miles now. So, we will see in about 5 to 7 years if I have a problem with my EGR system.

 

I have been following this thread with interest since I have just passed 100k miles.

I looked at my EGR flow with Techstream just to see what flow I have now. As the OP gives in his opening post the Min is 0.99 and the Max is 655.35. My flow from the last trip was 21.79 kPa.

It will be interesting to check this every now and then to see if it decreases.

 

Are all those value in kilo Pascals? I wonder if the progression from max to min is linear or logarithmic, ie: is your 21.79 alarmingly low, or it's typical to drop fast, then it goes slower. It'd be great if someone with a near-new Prius and Techstream could report a value for comparison.

I just did a quick but fruitless search for an EGR pressure XGauge (for reading on ScanGuageII, which I have). Starting to get motivated to look into Techstream.

Also thinking to try just unbolting everything I can on the EGR module, at both ends, and see if there's enough give in the coolant lines that the head end flange could be shifted for a look inside.

 

This is my first reading so I have no idea whether the flow value is low or not.

As you say it would be nice if someone with a new Prius and Techstream would chime in with their flow value to give us a benchmark.

 

Trying for the life of me to understand this install sequence. Really have a love/hate relation with the Toyota Repair Manual. I suspect there's one or two typos:



(I think I understand the objective, to get all flanges in full, stress-free contact.)

 

The complexity of service and repair is my motivation for waiting until the car "codes", then buy new parts to fix it. I'm not eager to take it apart just to take a look. Though I do understand the motivation to stay ahead of this. I may sell the car before 200,000 miles and it may never be an issue for me.

 

It's pretty much necessity to pull off all the windshield cowl components (including wiper motors), for half decent access. And raise the car, and remove the engine underpanel. And let the coolant drain, maybe schedule with coolant change.

Google "YouTube nutzaboutbolts spark plug" for a good explanation of cowl removal.

 

Might as well replace the spark plugs at the same time in that case.

 

With all that work involved, perhaps buying a used one on EBay would be a good deal. Here is one for $120 complete, and there are a few others

Buy it and put it on the shelf until the 100,000 mile mark. Replace the EGR, Spark Plugs, and antifreeze all at the same time.

2010 11 12 13 Toyota Prius EGR Valve 25620 37110 Adapter 25601 37010 | eBay

 

My sisters 2010, same old song, her cooler was plugged up pretty bad as well, she purchased a used one it to was clogged. I got it to my garage and placed it in my warm parts washer hose going into it and left it running all night long, the warm fluid running through it did the trick. Its been back in the car now for just under a year no more codes and running smoothly.

 

?warm parts washer? i had to look it up.

 

============================================================
Did you use an Ultrasonic Cleaner on the EGR Valve, EGR Cooler, or Both ???
Planning on using an Ultrasonic Cleaner with purple power on both, but concerned about the EGR Valve part, don't know if there is electronic components in there ???

 

There are some electrical components in the valve, and they're held on by very tenacious screws, I gave up trying to break them loose. I'd recommend a few squirts of brake cleaner at both ends of the passageway, and a bit of brushing, Keep the valve positioned so the electronics are at the top.