Trouble Code P0401?

Tiny
HSANO6294
  • MEMBER
After removing the EGR Valve, I looked into the EGR port on the intake manifold and down the EGR tube. While there is a little carbon buildup, it is nothing significant. It is possible there may be more buildup at the bottom of the tube as I cannot easily reach where it attaches to the exhaust manifold.

I tested the EGR Valve and it appears to be okay. The diaphragm looks solid. I pushed it up and put my finger on the port. It held it in the up position until I released my finger ten to fifteen seconds later. Is it worth replacing while I have it off? I have heard they last quite a while. I have to replace the EGR Valve gasket as it broke during removal.

While at the parts store looking at a replacement EGR Valve, I noticed that the range of motion on my old valve in the passageway was not as much as the new one. The diaphragm appeared to have full range of motion.

I decided to replace the EGR Valve. Upon startup, the check engine light did not come on. I will drive around the car for two hundred miles and bring it to be smog tested. I will update when that happens.

Do you have any other suggestions? I think I am approaching the limit of what I can do in my driveway. Thanks!
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Saturday, November 14th, 2020 AT 2:29 PM (Merged)
Tiny
KEN L
  • ADMIN
Hello,

Here is a test you can do to see if the EGR is getting exhaust. Remove the valve and start the engine for a second and see if you hear exhaust coming out, you will know it becasue it will be loud.

Please let us know what you find.

Cheers, Ken
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Saturday, November 14th, 2020 AT 2:29 PM (Merged)
Tiny
HSANO6294
  • MEMBER
Replacing the EGR Valve allowed my car to pass the California smog test. As a side benefit, though the engine was already running pretty smoothly, each successive step (replacing the Vacuum Modulator, replacing the EGR Valve) had the engine running even smoother.

The range of motion difference between the old and new EGR Valve in the exhaust gas passage didn't look like a lot, but it must've made a difference operationally.

Thanks to HMAC300 and 2CARPROS KEN for their advice!
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Saturday, November 14th, 2020 AT 2:29 PM (Merged)
Tiny
SDAVIDSONJR
  • MEMBER
  • 1997 TOYOTA CAMRY
  • 4 CYL
  • FWD
  • AUTOMATIC
  • 169,883 MILES
SImple question that I hope has a simple answer. I am looking to pinpoint the problem so I don't get overcharged for the repair. So my question is, what does error code P0401 really mean? It says EGR Flow Insufficient Detected but what does that really mean? What part actually failed if any? How much would something like that cost to get fixed?
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Saturday, November 14th, 2020 AT 2:29 PM (Merged)
Tiny
MASTERTECHTIM
  • EXPERT
Im giving you what most likely is the problem. The egr solenoid fail on this car frequently and should cost about 150 to 200 to repair at a shop
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Saturday, November 14th, 2020 AT 2:29 PM (Merged)
Tiny
KEN L
  • ADMIN
Good to hear, please use 2CarPros anytime we are here to help.

Cheers, Ken
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Saturday, November 14th, 2020 AT 2:29 PM (Merged)
Tiny
SDAVIDSONJR
  • MEMBER
Is this something that I could fix or is that not recommended?
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Saturday, November 14th, 2020 AT 2:29 PM (Merged)
Tiny
MASTERTECHTIM
  • EXPERT
You can fix it. Now I cant say for sure this will fix it but in most cases it does. The valve is located at rear of engine and you must access it under the vehicle. Not alot of room to move.
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Saturday, November 14th, 2020 AT 2:29 PM (Merged)
Tiny
=LIGS=ELVIS
  • MEMBER
I removed and cleaned an egr on the exact same vehicle this evening. It can all be done "top side" with the proper extending tools and a long arm.

I am trying to help a buddy with his emissions issues. He says he had the egr replace just a few months ago. Are we looking at a vacume leak. Or another culpret? I am not familiar with Toyotas inparticular. If the egr has been replaced to no avail. Should th evaulve to the left of it get replaced too?
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Saturday, November 14th, 2020 AT 2:29 PM (Merged)
Tiny
MASTERTECHTIM
  • EXPERT
That and or the egr solenoid. The valve itself never fixes it, for some reason they dont go bad, 85 percent chance its the egr solenoid and 15 percent its the back pressure valve
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Saturday, November 14th, 2020 AT 2:29 PM (Merged)
Tiny
MRRELIZ7
  • MEMBER
  • 1996 TOYOTA CAMRY
  • 203,000 MILES
Smell
sometimes smoke
muffler noise or hesitation rattle sound
engine light on troubleshooting code when check does po401 damage engine
I think also there exaust leak in muffler cause of smell can it trigger po401
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Saturday, November 14th, 2020 AT 2:29 PM (Merged)
Tiny
HMAC300
  • EXPERT
Start and run engine at idle air shold escape form filter in pic. Check resistance of piece with engine off it shold be 33-39 ohms at 68 degrees then check for continuity between each pole and body of valve if there is replace it.
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Saturday, November 14th, 2020 AT 2:29 PM (Merged)
Tiny
JLBOWERS
  • MEMBER
  • TOYOTA CAMRY
1996 Toyota Camry 200334 miles 2200 engine where is the EGR? I have a code of P0401 Exhaust Gas Recirculation Flow Insufficient Detected. What do I do?
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Saturday, November 14th, 2020 AT 2:29 PM (Merged)
Tiny
FISHERMAN
  • MEMBER
Check the vacuum diagram sticker on the hood.

There you can find it.
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Saturday, November 14th, 2020 AT 2:29 PM (Merged)
Tiny
BUZZSAW
  • MEMBER
Make sure the switch over valve is working before replacing egr
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Saturday, November 14th, 2020 AT 2:29 PM (Merged)

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