EGR PO400 Trouble code still ON ?

[mrbrush]

Hi Guys, Hope someone can shed some light on this issue.

One day before leaving Brissie for Kimberly trip Engine light comes on .
I have the Obd Scanmaster program so 3 days later halfway to Alice springs I find DTC PO400.
No ill effect with driving and no limp mode So I clear it.
Each day it comes on then I clear it.
6 weeks and 12000k later I get home and remove the EGR valve body and clean all the sooty junk out.
Engine still runs fine but next day engine light back on PO400.
330,000k on the clock, Don`t know what it could be now ?
Have good vacuum at solenoid pipes, Checked All connectors,
What would a Mechanic charge to fix this issue ?
Thanks.

[outbackjoe]

If you already cleaned it all out then dodgy EGR valve I reckon.

[Blackdelux]

did you clean egr cooler?
have u put in a egr restriction plate without a hole?

[mrbrush]

If you already cleaned it all out then dodgy EGR valve I reckon.

It wasn`t really stuck, perhaps it`s possibly leaking ? .

[mrbrush]

did you clean egr cooler?
have u put in a egr restriction plate without a hole?

No block plate.
Cooler ? If it`s that long rectangular box, No didn't clean it.

[Blackdelux]

try cleaning Egr Cooler yes the long rectangular box,
while your there i would suggest egr restriction mod ,
look thread up for pros and cons

[mrbrush]

Thanks mate I`ll check it out.
Cheers

[hiluxsr]

Hey 'mrbrush' how did you end up going with the engine light/EGR? Did you find out what the problem was? Just wondering, because i have the same problem with mine. So bloody annoying having the engine light on. Would be fantastic if you have found the cause and could possibly give an update.

Much appreciated

[mrbrush]

Hey 'mrbrush' how did you end up going with the engine light/EGR? Did you find out what the problem was? Just wondering, because i have the same problem with mine. So bloody annoying having the engine light on. Would be fantastic if you have found the cause and could possibly give an update.

Much appreciated

Hi Mate, I took my ute in to Toyota for the spiral cable recall fix.
Asked service man to check it out while it was there.
They found the airflow meter was dusty. And cleared the engine light. Did more tests and told me it should be all good.
But three days later engine light comes back on. Same code PO400 .
Now they want the vehicle for 3 to 4 hours @ $130/hr to check it right out. I said get stuffed.
This is the best info I found to troubleshoot the problem http://www.moranbahweather.com/toyota/h ... f007x.html
I have checked and tested vacuum lines, diaphram holds vacuum, and the solenoid all is good.
I have a scanner to clear the code. But I`ve cleared it just by removing Positive terminal.
I` m guessing it is gunk or soot build up in the cooler or intake with 340k on the clock would be the problem. But I need time to pull it all apart. Maybe Christmas time.
Cheers

[hiluxsr]

Thanks mate, i ended up removing the entire intake side of things, throttle body, EGR, EGR cooler, manifold etc.. dissasembled everything i could and gave it a super clean. Found crap load of soot around the EGR and the EGR cooler was filthy. Took me a while to clear most of it out but worth doing. Car runs so much better and best of all the engine light has not come back on since.
Im guessing at 340k there will be quite a build up of soot around, i have 210k on the clock and it was filthy!
Best bet remove everything and give it a good clean before you take it into Toyota and see how you go from there. At $130 p/hr I'm sure that $$$ will come in handy elsewhere. If all your tests have come up fine and air flow meter is all good, shouldn't be a major problem.
When you do you have everything apart just make sure all those vacuum lines are in good nick while you're there.
Good luck

[mrbrush]

Hey. Did you have to a use crows foot spanners to remove the injector lines ?
Did you get new gaskets ?

Cheers.

[Shea]

Did you ever sort this out mrbrush?

[Gipsy]

Just as a side note with these EGR issues, I know of a 'fix' for Jeep engines with EGR problems where a simple resistor is placed in the sensor circuit which tricks the ECU into thinking the EGR is working within specified range, thus isolating the entire system. Any ideas if this has been mastered with 1kd engines?

[Gipsy]

I just found this online:

Delete EGR (Exhaust Gas Reheat/Recirculate) Valve function electronically by simply adding another resistor to the factory resistor - The Temperature Sensor on Air Flow Sensor is just a Resistor being cooled by the air flow. This simple process of cutting one wire & adding an extra Resistor tells the ECU to not activate the EGR.
Japanese car makes were facing their own Dieselgate scandal in March 2016, when the Japanese Govt tested their Diesel models & found they emitted many times higher than their claimed pollution levels. Toyota blamed the cold weather caused the vehicle emission controls (EGR) to switch off as quoted: Toyota “will continue to make improvements to reduce NOx emissions during on-road vehicle operation,” a company spokesman told the Wall Street Journal, with Nissan and Mitsubishi giving similar answers. It is believed cold weather may have affected the tests, with engines potentially switching off exhaust recirculation systems (EGR) as a protection measure. Diesel sales make up just 4% of the Japanese market.

This process of fitting an additional Resistor to the Temperature Sensor on the Air filter box (AAT) only switches off the EGR & does not interfere with other engine functions. The engine mixtures are calculated by another Air Temperature Sensor (IAT) located near the Inlet Manifold. This Manifold Temperature Sensor reads the actual Air Temperature after it has been compressed by Turbo & Cooled by Intercooler.

[Gipsy]

it does work on a jeep but it would be interesting to hear from any Hilux owners who have tried it. I'm not sure it would change any other settings because the ECU uses manifold temp and pressure (MAF/MAT/MAP) after the turbo so the air cleaner IAT doesn't seem to matter much. It may only change the outside temperature on the dash. Otherwise IAT isn't really important to the ECU.
It would be interesting to just put one in and see how it works. Anyone want to be a guinea pig?

[MrMoose]

Hi All,

I have a 2007 Toyota Hilux Kun26R Auto. I'm on my last nerve with this vehicle.

I keep getting a P0400 Error code come up.

I've cleaned the stinking thing about 4 times and still coming up with an error.

Does anyone know the operation of how the EGR system works? Like an in depth and detail explanation. I brought my car to Toyota and they told me that the VSV and VRV are broken letting the vacuum escape?

I have replaced almost everything on this car and I'm still coming up with P0400 error rather then me replacing more parts as I am not a parts change can someone point me in the right direction on getting this info?

Thanks.

[hiluxxury]

Gday MrMoose, this topic comes up a few times here... I've merged your question to try and keep things together.

Have a look at these:
https://www.youtube.com/watch?v=CsPfMhFCzP8

https://www.youtube.com/watch?v=qkMEqeIPY4I

[MrMoose]

Gday hiluxxury,

I've actually gone and replaced the whole EGR cooler with a new one and still P0400 is coming up. He says something interesting in the video that the EGR Cooler is used for two things
1. To cool down the exhaust gases and
2. Used as a Turbo boost dump.

I've noticed that the EGR bypass valve initially starts at the 12 o'clock position and momentarily goes to the 10 o'clock position and reverts back.

I'm starting to think it could be the VRV and the VSV as Toyota mentioned.

The reason why I say this is that the black cap/filter are broken on both the VRV and VSV (I didn't break them they were broken already when I purchased this vehicle). Maybe Toyota technician could be right in their diagnosis?

[hiluxxury]

Well that sent me down this rabbit hole:

https://www.4x4community.co.za/forum/sh ... in-3-0D-4d

and I'm not any wiser

[MrMoose]

Well,

I've replaced the VSV with a genuine Toyota Part #9091012184 (in case anyone wants to know its located on a bracket just below the EGR Bypass Valve above VSV #1) and I've taken it for a ride and the damn code came back up.

Well, Toyota was wrong in there diagnosis of the VSV #2. I'm just waiting for the VRV to be delivered and replace that (which I highly doubt that it's the culprit but we'll see) and pray that it will get rid of the P0400.

Here's a strange thing that happened while reading live data from my cheap diagnostic tool. I've noticed when I cleared the DTC from the ECU and started the engine everything seemed to be normal. According to some other posts I've read on here normal MAF reading at idle should be between 8-10 g/s which mine was reading. While driving and watching how the reading fluctuates for the MAF sensor I came to stop and let it idle in park. I then realised that the MAF reading was around 14-16 g/s. So, I got out of the car and noticed that the EGR bypass valve (the valve after the EGR cooler) was in the 12 o'clock position (which I believe this means a closed position). I thought maybe it's stuck but when I moved it by hand it came down with ease and went right back to 12 o'clock position. Other thing I noticed is that when I pulled the bypass valve down at around 10 o'clock my MAF reading went back down to the original 8-10 g/s. Once I let it go the MAF reading shot right back around 14-16 g/s.

There has to be something that the ECU is not liking and shutting down the EGR valve. I just can't pinpoint for the life of me but I won't stop learning about how this EGR operates at what condition.

On to replacing the VRV when it gets delivered until then I shall be researching in case I'm missing something.

Cheers.