I have had a P0401 code for almost a year now. I have read countless threads. Tried a few things as suggested by forum members and I have not been successful in rectifying the issue. So far I have replaced EGR Valve, EGR Vacuum Solenoid & removed IM along with TB for a thorough cleaning of EGR ports etc. I'm wondering now if all of my vaccum hoses are properly routed. Can anyone supply a full diagram showing the proper routing scheme for the entire egr system or add any suggestions? All help will be greatly appreciated. I own a 2003 Mitsubishi Lancer ES, NA.

P.S. I do not plan to block off my EGR

 

Here's the routing, it's from a 04, but i think it's still the same. If the routing isn't the problem, I'd start checking wiring and connectors.

 

Thanks a lot, do you know if the egr connects to the green labeled or white labeled side on the vacuum control valve?

 

Green to tb, white to egr

 

Ah thanks, will double check.

 

I noticed another solenoid valve in the egr system. Mitsubishiparts has it labeled as solenoid #1 & #2 (I already replaced). So based on this, am I to assume that the 4G94 has 2 vacuum solenoid valves within the egr system? I may go about testing this valve also. Once again, all suggestions to help fix my issue will be greatly appreciated.

Here's is a shot of my egr system labelling the valves:

 

#2 in the pic is the purge solenoid for the evap system, if you already replaced that one, you just replaced the wrong one is all. Replace #1 and the code should be history. Part # is MR127520.

 

Are you sure? I just double checked and the part # you supplied is what I already replaced which is #2 in the pic.
The purge solenoid is #1.

 

Yeah, you're right, sorry about that, for some reason I thought you were taking the pic from the firewall towards the front of the car. I need to stop trying to think so early in the morning Since you cleaned just about everything there is to clean system wise, and replaced the solenoid, I'm wondering if you might have a restriction in the line.

 

I'd check up at the throttle body. Another guy had the same issue and where the line connected at the throttle body. There was a pin hole there plugged with carbon.

 

It's cool, I was wondering if that's what you thought about how I took the pic lol. Funny! I'll probably try the harness to see what happens. I'm out of ideas here.

 

Even though I doubt it, I'm wondering if one of the lines may be clogged. The ID of those lines is pretty small, but that would take quite a while of neglect to get in that condition. I haven't had any egr issues with my car so I haven't done that much in that regard, but the harness is a possibility. Typically the engineers are smart enough to keep away from sharp angles and vibration (well except for my old bonneville, the tps connector made a full 180 to plug into the tps, engineering genius that was lol), but if there's a short in the wires coming off the harness that may be it. Check the wires out for any chafing. I'm running out of ideas too.

 

https://www.evolutionm.net/forums/sh...=580594&page=2

 

Thanks, I know that throwing a bunch of parts at this is not the best way to solve this issue but I may have to do that. Believe me when I say I have tried everything. I am 100% sure all hoses are good but just to make sure I will replace them all.

 

I would try what 02mod suggested first, you don't want to start spending money if you don't have to.