PO-401 Insufficent egr flow - Toyota Tundra Forums : Tundra Solutions Forum

RAV4GUY · #1 (**permalink**) 08-30-2006, 03:03 PM

Hi Everyone,

I'm new to this forum and this is my first posting. I have a 2000 Toyota RAV-4. 4 cylinder, 2 wheel drive, 4 door. Yesterday the check engine light came on. The code that I'm getting is PO-401 insufficent egr flow. Can you please tell me how to clean the egr valve? What chemical should I use as a cleaner? How do I clean the long pipe that is attached to the bottom of the valve? I looks like it goes down deep into the engine. Besides cleaning the egr valve and pipe what are some other things I should do or check to clear the code? What is an egr sensor? Does my car have one? Would the sensor have anything to do with the error code I'm getting?

Thank you all in advance.

THarms · #2 (**permalink**) 08-31-2006, 12:06 AM

please re-post your question in the RAV4 forum... you will probably get more responses.

My guess is that the EGR position sensor has gone bad (the same thing just happened on my wife's 99 Solara). Cost me about $35 for a new sensor and took about 10minutes to install. The sensor is the little electronic piece that sits on top of the EGR valve that the wires plug in to... mine came off with removal of only 3 screws.

mustang67408 · #3 (**permalink**) 08-31-2006, 12:34 AM

Quote:

Originally Posted by RAV4GUY

Hi Everyone,

I'm new to this forum and this is my first posting. I have a 2000 Toyota RAV-4. 4 cylinder, 2 wheel drive, 4 door. Yesterday the check engine light came on. The code that I'm getting is PO-401 insufficent egr flow. Can you please tell me how to clean the egr valve? What chemical should I use as a cleaner? How do I clean the long pipe that is attached to the bottom of the valve? I looks like it goes down deep into the engine. Besides cleaning the egr valve and pipe what are some other things I should do or check to clear the code? What is an egr sensor? Does my car have one? Would the sensor have anything to do with the error code I'm getting?

Thank you all in advance.

I would suggest replacing the EGR modulator and EGR VSV (under intake manifold).
Apply vacuum to the egr valv , if the engine stumbles or dies the egr is not plugged and you probably have a bad modulator and/or vsv. the vsv's are known for sticking closed, and the modulator are known for either becoming plugged with carbon or rupturing the diaphram.
Make sure you have ported vacuum from the 2 ports on the throttle body to the modulator.

new_waverider · #4 (**permalink**) 05-02-2007, 08:16 AM

I too am having the repeated code on my 2000 Camry LE-4 cylinder after having replaced the PCV valve and EGR regulator switch. What related parts should I have the mechanic check? Thanks in advance for your reply.

mustang67408 · #5 (**permalink**) 05-02-2007, 09:18 AM

Quote:

Originally Posted by new_waverider

I too am having the repeated code on my 2000 Camry LE-4 cylinder after having replaced the PCV valve and EGR regulator switch. What related parts should I have the mechanic check? Thanks in advance for your reply.

I would suggest replacing the EGR modulator and EGR VSV (under intake manifold).
Apply vacuum to the egr valve , if the engine stumbles or dies the egr is not plugged and you probably have a bad modulator and/or vsv. the vsv's are known for sticking closed, and the modulator are known for either becoming plugged with carbon or rupturing the diaphram.
Make sure you have ported vacuum from the 2 ports on the throttle body to the modulator.Clea Throttle body to be sure.