Failed smog +egr valve 2001 Mitsubishi montero sport

code p0400 refers to exhaust gas recirculation (EGR) system--flow malfunction===causes--hoseleak/blockage, basic setting not carried out (if applicable)--wiring---EGR valve--EGR solenoid---ECM
As the EGR unit is susceptepable to corrosion. Check it out or replace it

there is no air injector pump on your vehicles Vehicle Emission Control Information sticker (VECI) there are fuel injectors and evapoative canister, oxygen sensors and egr valve, egr vacuum control valve, manifold absolute pressure sensor, and a pcv valve and some other usual sensors hope this helps

Doesn't sound right

You need to know in detail what testing was done
or get it out of there ---if they won't allow you into the
service bay to talk to the tech that worked on it,not
on the phone or in an office for the Dog & Pony Show

Trouble Code: P0403

EGR Control Circuit Malfunction
Possible Causes:


EGR solenoid control circuit is open or shorted to ground . EGR solenoid power circuit is open (check power from relay) . EGR solenoid is damaged or has failed . PCM has failed .

Taken from Smog tips:

The Exhaust Gas Recirculation system is designed to reduce NO. The EGR system consists of an EGR valve, EGR pressure sensor, vacuum hoses, and one or more vacuum switching valves or solenoids. Later model vehicles may be equipped with electronically controlled EGR valves, which do not require vacuum lines or switching solenoids. Electronic EGR systems will have these components built in.


Changing the sensors should work.. also change the O2 sensor(s). I know in my 2002 there were 2 of them and they are not cheap.

Sounds like to me you have a faulty EGR vacuum solenoid which regulates the vacuum pressure sent to the EGR valve.

check owners manual for fuse for emissions devices

The Cat code could have cleared itself if the computer doesn't detect a problem anymore. Fix the EGR problem as it is still active.

its an egr CIRCUIT MALFUNCTION which means can be any type of problem with the whole circuit -- wiring --connections fuses relays etc not just the egr valve more than likely the valve was good need to check and test the whole egr system

your code is 1867