1996 toyota camery code po401

In a word with only one syllable; No.

po401 is insufficient air flow from EGR valve. check the vacuum hoses from egr, if ok, remove or test the egr valve itself and try to clean it out. Good-Day! It may just be sticking, from carbon buildup.

Try to clean,it is EGR valve.Tubing too.

cleanout egr valve and troutle body . Or replace egr with new one, clean, check vacumm lines , check for clogged check , depending on modle of car you can pippoint problem as some have a common part problem depeding with make of car. But all have to do with exaust system. Insufficient flow exaust flow. Im not an expert, all I know it is related to this, I have it myself so im googling it.

Ford EGR valve

The OBDII fault code P0401 means that the engine computer has detected that the Exhaust Gas Recirculation (EGR) system flow is insufficient. Read more how the EGR system works below. What could cause the code P0401 - clogged or restricted EGR passages
- faulty EGR valve
- EGR valve stuck closed
- problems with the DPFE sensor (Ford)
- problems with hoses to the DPFE sensor (Ford)
- problem with the EGR vacuum switching valve (Toyota)
- clogged catalytic converter
- carboned up EGR temperature sensor
- vacuum supply issues at the vacuum-operated EGR valve
- electrical problems with the EGR valve control circuit
- engine computer problems
helpful website helps you with pinpoint and sou;ution related to auto make and model shows you most common cause of code reading.
www.samarins.com

here's a link to some information on the codes you asked about
P0401
P0340

good luck!

p0402 is egr valve flow excessive. egr valve needs cleaned or replaced also check wires etc. to vavle.

depending on your model, there may be a solenoid valve that turns the vacuum to the egr valve on. If the solenoid fails, the egr valve will not open. Follow the vacuum line on the egr valve--does it go to a solenoid valve? If yes, apply 12 volts directly to the solenoid blades to see if it clicks open. If it doesn't click, replace the solenoid.

Recheck all the vacuum lines near the EGR solenoid. The new codes are for the EVAP emissions system. they are codes for incorrect purge flow. You may have left a vacuum line of, switched a couple of lines or forgot to plug something back in.

I’m happy to assist further over the phone at https://www.6ya.com/expert/jeremy_d728a59f986299fa

I believe this code is insufficient EGR flow. On this engine, the passages to the EGR valve often become carboned up and cause this code. Remove the EGR valve and inspect the passages to see if they need to be cleaned.

Check for air leak into system after MAF.

Check for

vacuum leaks on intake manifold,

the air tube between the air filter.

intake manifold vacuum hose.

===
clean throttle plate with Berryman carburator cleaner

SEE sample picture HERE
===


Check for loose or no connected vacuum hose(s).


Take it for a test drive.


Please rate my answer if it's useful to you.


Cheers,

Mustgo