Guess I'll have to sell it., EGR Options

[ST204GT83]

Today is my last day of legal driving. We found the new vsv I bought was faulty, so I bought another one, we tested it, it works. Check engine light came back on last night, still egr. Replaced all the necessary parts, egr, modulator and vsv, new vacuum lines, everything is clean. We are truly at a loss. Maybe 02 sensor? I read about it. P0401. Never ending. This sucks.

[slavie]

Today is my last day of legal driving. We found the new vsv I bought was faulty, so I bought another one, we tested it, it works. Check engine light came back on last night, still egr. Replaced all the necessary parts, egr, modulator and vsv, new vacuum lines, everything is clean. We are truly at a loss. Maybe 02 sensor? I read about it. P0401. Never ending. This sucks.

Did you replace it with an OEM one? There is a known issue with aftermarket EGR VSV's on 5SFE, and many folks have had issue with aftermarket valves.
Also make sure you re-connect the vacuum lines correctly after the installation of the new valves. It's easy to switch them around. I learned that the hard way

This post has been edited by slavie: Mar 2, 2018 - 12:44 PM

[slavie]

Today is my last day of legal driving. We found the new vsv I bought was faulty, so I bought another one, we tested it, it works. Check engine light came back on last night, still egr. Replaced all the necessary parts, egr, modulator and vsv, new vacuum lines, everything is clean. We are truly at a loss. Maybe 02 sensor? I read about it. P0401. Never ending. This sucks.

Did you replace it with an OEM one? There is a known issue with aftermarket EGR VSV's on 5SFE, and many folks have had issue with aftermarket valves.
Also make sure you re-connect the vacuum lines correctly after the installation of the new valves. It's easy to switch them around. I learned that the hard way

I'm gonna repeat my own question one more time. Again, the EGR vacuum switching valve, as is the case with other VSV's, draws a metered amount of vacuum, and this vacuum draw is what ECU detects through MAP sensor to throw codes (as I explained in my 2nd post here, which was also ignored). Which one did you put in? OEM, or aftermarket garbage?

[ST204GT83]

Today is my last day of legal driving. We found the new vsv I bought was faulty, so I bought another one, we tested it, it works. Check engine light came back on last night, still egr. Replaced all the necessary parts, egr, modulator and vsv, new vacuum lines, everything is clean. We are truly at a loss. Maybe 02 sensor? I read about it. P0401. Never ending. This sucks.

Did you replace it with an OEM one? There is a known issue with aftermarket EGR VSV's on 5SFE, and many folks have had issue with aftermarket valves.
Also make sure you re-connect the vacuum lines correctly after the installation of the new valves. It's easy to switch them around. I learned that the hard way

I'm gonna repeat my own question one more time. Again, the EGR vacuum switching valve, as is the case with other VSV's, draws a metered amount of vacuum, and this vacuum draw is what ECU detects through MAP sensor to throw codes (as I explained in my 2nd post here, which was also ignored). Which one did you put in? OEM, or aftermarket garbage?

First one was aftermarket, second one I got at autozone for $70, the guys at the shop also put on another one on with no result. Three have been used.

[slavie]

Today is my last day of legal driving. We found the new vsv I bought was faulty, so I bought another one, we tested it, it works. Check engine light came back on last night, still egr. Replaced all the necessary parts, egr, modulator and vsv, new vacuum lines, everything is clean. We are truly at a loss. Maybe 02 sensor? I read about it. P0401. Never ending. This sucks.

Did you replace it with an OEM one? There is a known issue with aftermarket EGR VSV's on 5SFE, and many folks have had issue with aftermarket valves.
Also make sure you re-connect the vacuum lines correctly after the installation of the new valves. It's easy to switch them around. I learned that the hard way

I'm gonna repeat my own question one more time. Again, the EGR vacuum switching valve, as is the case with other VSV's, draws a metered amount of vacuum, and this vacuum draw is what ECU detects through MAP sensor to throw codes (as I explained in my 2nd post here, which was also ignored). Which one did you put in? OEM, or aftermarket garbage?

First one was aftermarket, second one I got at autozone for $70, the guys at the shop also put on another one on with no result. Three have been used.

MAKE SURE the vacuum lines are connected correctly to the EGR VSV. They are VERY easy to switch, and you will 100% guaranteed get a CEL if you do.

Here's the OEM VSV - $77:
https://parts.toyotaofcoolsprings.com/oem-p...alve-2586074050
The $70 from AZ is same crap as any other aftermarket ones, and likely what the shop tried.

Here is a fantastic video of Toyota ERG system diagnosis (from a Corolla, same operation and diagnosis):
https://www.youtube.com/watch?v=WOSFmKY15SU
It also answers your question about why the 2 vac ports on the throttle body are blocked by the gasket - they only open when throttle is open, not all the time.

For ECU wiring, it's pin #23 on the 26-pin (largest) connector. Here's a wiring FSM from a Camry, look at page 90 (same pinout, though wire color I think is different):
http://www.josvandijken.nl/downloads/pdf/b...oyota_camry.pdf

If you do all of the above and everything checks out (with OEM vsv), then replace ECU (with identical P/N). Electronic components within the ECU "dry up" and can start acting up. There have been cases where ECU replacement solved the P0401 code, here:
http://www.toyotanation.com/forum/103-camr...ml#post12813250

[ST204GT83]

Today is my last day of legal driving. We found the new vsv I bought was faulty, so I bought another one, we tested it, it works. Check engine light came back on last night, still egr. Replaced all the necessary parts, egr, modulator and vsv, new vacuum lines, everything is clean. We are truly at a loss. Maybe 02 sensor? I read about it. P0401. Never ending. This sucks.

Did you replace it with an OEM one? There is a known issue with aftermarket EGR VSV's on 5SFE, and many folks have had issue with aftermarket valves.
Also make sure you re-connect the vacuum lines correctly after the installation of the new valves. It's easy to switch them around. I learned that the hard way

I'm gonna repeat my own question one more time. Again, the EGR vacuum switching valve, as is the case with other VSV's, draws a metered amount of vacuum, and this vacuum draw is what ECU detects through MAP sensor to throw codes (as I explained in my 2nd post here, which was also ignored). Which one did you put in? OEM, or aftermarket garbage?

First one was aftermarket, second one I got at autozone for $70, the guys at the shop also put on another one on with no result. Three have been used.

MAKE SURE the vacuum lines are connected correctly to the EGR VSV. They are VERY easy to switch, and you will 100% guaranteed get a CEL if you do.

Here's the OEM VSV - $77:
https://parts.toyotaofcoolsprings.com/oem-p...alve-2586074050
The $70 from AZ is same crap as any other aftermarket ones, and likely what the shop tried.

Here is a fantastic video of Toyota ERG system diagnosis (from a Corolla, same operation and diagnosis):
https://www.youtube.com/watch?v=WOSFmKY15SU
It also answers your question about why the 2 vac ports on the throttle body are blocked by the gasket - they only open when throttle is open, not all the time.

For ECU wiring, it's pin #23 on the 26-pin (largest) connector. Here's a wiring FSM from a Camry, look at page 90 (same pinout, though wire color I think is different):
http://www.josvandijken.nl/downloads/pdf/b...oyota_camry.pdf

If you do all of the above and everything checks out (with OEM vsv), then replace ECU (with identical P/N). Electronic components within the ECU "dry up" and can start acting up. There have been cases where ECU replacement solved the P0401 code, here:
http://www.toyotanation.com/forum/103-camr...ml#post12813250

Thank you for all your information sir, I really appreciate it!