Mar 2, 2018 - 10:54 AM
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Enthusiast ![]() Joined Mar 6, '17 From Sacramento Currently Offline Reputation: 0 (0%) |
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.
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Mar 2, 2018 - 12:43 PM
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Enthusiast ![]() ![]() Joined May 2, '15 From NY Currently Offline Reputation: 3 (100%) |
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 |
Mar 21, 2018 - 8:44 AM
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Enthusiast ![]() ![]() Joined May 2, '15 From NY Currently Offline Reputation: 3 (100%) |
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? |
Mar 21, 2018 - 9:42 AM
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Enthusiast ![]() Joined Mar 6, '17 From Sacramento Currently Offline Reputation: 0 (0%) |
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. |
Mar 21, 2018 - 11:46 AM
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Enthusiast ![]() ![]() Joined May 2, '15 From NY Currently Offline Reputation: 3 (100%) |
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 |
Mar 21, 2018 - 12:55 PM
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Enthusiast ![]() Joined Mar 6, '17 From Sacramento Currently Offline Reputation: 0 (0%) |
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! |
Mar 22, 2018 - 5:12 PM
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Enthusiast ![]() Joined Mar 6, '17 From Sacramento Currently Offline Reputation: 0 (0%) |
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! Slavie, do you understand what I was saying about the intake manifold and throttle body? |
ST204GT83 Guess I'll have to sell it. Mar 2, 2018 - 10:54 AM
djgeo05 I have been fighting this same code for almost a y... Mar 2, 2018 - 4:22 PM
ST204GT83 QUOTE (djgeo05 @ Mar 2, 2018 - 4:22 ... Mar 2, 2018 - 6:39 PM
Smaay have you checked the wiring from the ECU to the VS... Mar 2, 2018 - 8:41 PM
ST204GT83 QUOTE (Smaay @ Mar 2, 2018 - 9:41 PM... Mar 3, 2018 - 12:35 AM
micronian That P0401 code is a bitch. I've had to deal w... Mar 11, 2018 - 3:07 AM
Bitter How would a component from the evap system affect ... Mar 11, 2018 - 9:01 AM
ST204GT83 QUOTE (Bitter @ Mar 11, 2018 - 10:01... Mar 11, 2018 - 9:44 AM
ST204GT83 Bitter, are there supposed to be holes for vacuum ... Mar 11, 2018 - 9:52 AM
Smaay the charcoal canister has NOTHING to do with the E... Mar 11, 2018 - 8:04 PM
ST204GT83 QUOTE (Smaay @ Mar 11, 2018 - 8:04 P... Mar 12, 2018 - 1:26 AM
slavie Have you actually tested the EGR system? The facto... Mar 11, 2018 - 8:29 PM
97GTinKC Possible causes for P0401:
EGR passage clogged ... Mar 20, 2018 - 1:52 PM
NgoFcukinWay Had that issue on a '99 camry we owned. I put ... Mar 20, 2018 - 5:28 PM
ST204GT83 QUOTE (NgoFcukinWay @ Mar 20, 2018 - 6... Mar 20, 2018 - 7:52 PM
ST204GT83 Just got my oem vsv delivered, and my ecu is on th... Mar 30, 2018 - 10:15 PM
ST204GT83 Hey everyone, got good news, EGR light is gone... Apr 6, 2018 - 9:51 AM
ST204GT83 Alright, set catalyst monitor today, went to smog,... Apr 10, 2018 - 6:15 PM![]() ![]() |
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