Need a wiring diagram for a 1998 toyota camry for the vsv. replaced the transducer and vsv still getting code p0401 erg flow insufficient. any suggestion?

Hi Joe

Like all solenoid valves, you can clean them with throttle body cleaner and then test the solenoid electronically with a 12 volt supply.

P0401 Exhaust EGR Flow Insufficient

Toyota Nation Forum https://www.toyotanation.com > threads > p0401-exha...
May 1, 2014 - The sensor is how the ECM determines there's insufficient EGR flow. It's on the intake-side of the system and if not enough exhaust-gases flow ...

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P0401 : EGR Flow Insufficient on 1996 Toyota Corolla

OBD-Codes.com https://www.obd-codes.com > forums > viewtopic
Jan 20, 2007 - on EGR codes, we recommend replacing the EGR, vacuum modulator and VSV (if equipped) and cleaning out the carbon buildup to the intake from the ...
If that finds nothing wrong, remove the EGR valve and bypass tube and check them for cleanliness and blockages. If they are blocked, follow your maintenance manual's instructions for cleaning them out so you do not damage the valve, then replace them and reset the ECM.

Insufficient EGR Flow - P0401 Code - Toyota

Anon, disconnect vacuum lines,wires, etc. and unbolt EGR from intake shown in 4th video link. Check the attached links,instruction and guides, Good luck
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OBD II Trouble Code P0401 Insufficient EGR Flow
How to Fix P0401 on 1996 Toyota Avalon Testing The EGR Modulator Valve

The code P0401 means P0401 Exhaust Gas Recirculation Flow Insufficient Detected.
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airbag reset tool also check fault code!

P0401= Exhaust Gas Recirculation "A" Flow Insufficient Detected
for more info pls refer to this link http://www.obd-codes.com/p0401
this isn't really nothing major to worry about it just a emission code

P0401-Insufficient flow in the exhaust gas recirculation system (EGR-valve). Check your gas cap for cracked seal, check EGR valve (make sure all vacuum hoses aren't leaking), check also VSV (vacuum switching valve) for proper operation. Its best to get an owner's manual or an experienced mechanic to diagnose!!hopefully this helpd

P0401 OBD-II Trouble Code
Insufficient EGR Flow
What does that mean?
EGR stands for Exhaust Gas Recirculation. It is part of the vehicle emmissions system, and is used to reduce combustion temperature and pressure to control Oxides of Nitrogen. There are generally three parts to the EGR system: the EGR valve, an actuator solenoid, and a differential pressure sensor (DPF). These things work together to deliver the correct amount of recirculation based on engine temperature, load, etc. The P0401 code means that OBD detected an insufficient amount of EGR.

There is a vsv (vacuum switching valve) located under the intake manifold that goes bad very often causing this code. Its hard to get to. Follow the hoses from the black plastic round valve(egr modulator) you see next to the EGR valve to find the vsv.

replace the vsv that has the vacuuum hose running from it to the egr valve

I'm assuming that it is a four cyl.The p0401 code is for insufficient egr flow.Most of the time it is the egr vsv valve (vsv means vacuum switching valve)which is what controls the vacuum to the egr valve to open it.It is kind of hard to get to as it is on the block under the head on the back side.If you follow the hose from the egr valve it goes to the vsv.I have also seen mice eat holes in the vacuum line which would also give you problems.I hope this help and let me know if you have anymore questions