Cel (p0401)

JoeCamry · #1 (**permalink**) 07-20-2005, 05:49 PM

2000 Camry LE (v4).

Have been fighting with a CEL that is a code P0401 (EGR Insufficient flow detected) for several months now. Car runs great...no problems that I can see/feel/hear/etc... Only exception is the CEL.

When I first had the CEL appear, I took it up to Autozone and had the code read...P0401. On the top of the list is EGR valve. a little while later, I replaced the EGR valve and had the code reset. Two days later the CEL comes back...P0401 again. Next item I replaced was the ECT (Engine Coolant Temperature) sensor and had the code reset. Not quite a day later, the CEL comes back...Yes, P0401. Next item I replaced was the EGR Modulator valve and had the code reset. One day later, the P0401 comes back. Which brings me to the present day...

I have purchased the next part on the list... An EGR VSV. I have looked at Haynes and there appears to be several views of this for different models, but I can't seem to find on the car what the fine folks at Toyota gave me. Autozone didn't have the VSV, nor the modulator btw.

Like I said, the car is running great thus far, so I'm not getting too worried at the moment, but just not comfortable with this CEL hanging around.

Does anyone have a GOOD photo/diagram/etc... of this part/location/etc... that they could respond with? I'd appreciate it. Bout to pull my hair out with this thing.

JoeCamry · #2 (**permalink**) 07-20-2005, 05:50 PM

Oh yeah, forgot to mention I changed 3 hoses also. Hose from EGR to modulator. 2 hoses from the modulator to their respective connections.

dyogim · #3 (**permalink**) 07-20-2005, 07:09 PM

Try this: http://www.obd-codes.com/trouble_cod...n-flow-egr.php

Eddie · #4 (**permalink**) 07-20-2005, 08:58 PM

Since you basically replaced everything else,it's most likely the EGR valve itself.

JoeCamry · #5 (**permalink**) 07-21-2005, 11:00 AM

I have researched the code in several places and am reasonably sure what the possibilities are. Oh and Eddie, like I mentioned, I have already replaced the EGR valve. I have done the EGR valve, EGR modulator, and Engine Coolant Temperature sensor. Of all the places I have found, the next item on the list is the EGR Vacuum Switching Valve or VSV. Like I mentioned, I purchased one yesterday from the dealer. I thought I knew the general vacinity this sucker is located, but upon multiple visual inspections, I cannot seem to find it on my car. What I had asked is if somebody either has or knows where I could get a good photo of the original part and location, etc...

Thanks.

Eddie · #6 (**permalink**) 07-21-2005, 05:42 PM

Quote:

Originally Posted by JoeCamry

I have researched the code in several places and am reasonably sure what the possibilities are. Oh and Eddie, like I mentioned, I have already replaced the EGR valve. I have done the EGR valve, EGR modulator, and Engine Coolant Temperature sensor. Of all the places I have found, the next item on the list is the EGR Vacuum Switching Valve or VSV. Like I mentioned, I purchased one yesterday from the dealer. I thought I knew the general vacinity this sucker is located, but upon multiple visual inspections, I cannot seem to find it on my car. What I had asked is if somebody either has or knows where I could get a good photo of the original part and location, etc...

Thanks.

Woops,sorry I missed that

Someone @ work has a Camry,I'll see if he'll let me look under the hood to find the VSV. If it were a V6 I could've told you exactly where it is.

tedy · #7 (**permalink**) 01-31-2007, 10:24 AM

I have recently bought a Camry 97, the cel went on after a few days. Whould you please let me know how can I figure out if the problem is with the VSV and how to replace it? What did you finally do about your case?
Thanks,

tedy · #8 (**permalink**) 01-31-2007, 10:25 AM

I forgot to mention that the code is p0401

mike10872 · #9 (**permalink**) 12-03-2007, 09:58 PM

On my 97 Camry 2.2 4cyl, I've replaced with all new dealer parts the EGR Valve, EGR Modulator and the VSV trying to get rid of that dreaded P0401 code. Since I changed all three related parts, is there anything else I can look for? BTW, I was able to get NYS inspection after driving about 20 miles, now the code is back.

maxxflow · #10 (**permalink**) 06-24-2008, 03:27 PM

Hi everyone, new to this forum: Joe, the vsv is located located toward the back of the engine, right underneath the intake manifold. It is very hard to reach. You might have a better shot at replacing the part by removing the front passenger side wheel and working from the wheel well. There are some pix of the location, just do a search on this forum and you will find them. I suck at adding links otherwise I would have. Hope this helps.

njerald · #11 (**permalink**) 06-24-2008, 04:32 PM

Gotta love all these owners who just start replacing parts rather that follow a troubleshooting matrix in their Factory Service Manual.

mailman · #12 (**permalink**) 07-03-2008, 04:41 PM

Nobody seems to mention the sensor. I have a V6 1996 and have the same code. The car runs great. I am going to try to replace the sensor. Has anyone had success with this in the past?

Mailman

rom1law · #13 (**permalink**) 07-08-2008, 10:30 PM

hi, thanks for the great post. i too had a p0401 error. i first replaced the modulator. did not work. next i paid to have my egr valve removed and cleaned. did not work. i then had the vsv replaced (i was told by the dealership that this part is an electrical device, see below). it solved the problem.

also, i had a problem with the turn signal prior to replacing the vsv. i got a very fast blinking light when i engaged the right or left indicator. this only happened when the head lights were engaged. replacing the vsv fixed this problem too. i dont know much about electrical components and how they work, but this may have been a symptom of a defective vsv. thanks for the post.