Well originally I wanted the OP to chime in but at this point, anyone who's had this CEL and was able to resolve it.

Any how, thanks much for the info jeremy_ton, I will definitely look more into this solution as well.

 

I'm pretty frustrated right now. The code has come back. It is not an air leak after the MAF. That is sealed up. I'm wondering if my RRM headers are not properly fitted to my exhaust. That would be my fault if it is. My symptoms are, SES light, P0171 code thrown, on cold start the engine boggs way down almost to a stall. Once warm all is well. Any takers on this issue?

 

I'm still fishing this one out too. The last couple of times this code came on, it clears itself.

 

If you guys have not done so already, check the vacuum line going to the fuel pressure regulator. they are known to pop off and will cause your trims to get screwy under idle / low load and the car will go stupid lean under boost.

 

Thanks man!

May have found out what's been causing my CEL (P0171). Got the car on a lift and found out I have an exhaust leak.

 

Turns out t he RRM Headers I got back in February have a significant hole in the weld. I just got off the phone with RRM and they suggested I have someone weld that hole up. I hope that is what is still giving me P0171. I've been fighting this code ever since I got the headers. It all makes sense now. It is either the hole or a bad gasket causing the leak. Hopefully.... I'll keep y'all up to date.

 

did you find out exact problem im havin the same issues

 

For me my problem was an exhaust leak. The flex pipe below the header had a torn gasket, and the actual header had a small hole. I fixed the header and will put it back on today with a new gasket. Hopefully the code will be gone. I'll keep you posted...

 

Mine was right where the downpipe connects to the test pipe..............gasket is pretty shot and will be replacing it real soon! Hopefully this should take the code way...... according to the tech manual.

 

Well for me P0171 was not an exhaust leak after all. Got all gaskets replaced and small hole in header weld filled. The code came back and today I found that 2 of my spark plugs had been overtightened and the gaps were closed. I fixed them and the car is running great and code free. I will keep you posted if something else turns up.

 

keep us updated....so it could of been the spark plugs?

 

Had no problems with any codes just 1 time rear o2 sensor for over 4 years! lol, lately I got p0121 code and i think i took care of that, and my Emission card came in next day! LOL so when i took care of p0121, today i got another code P0171.... how fun is that?

I dont think p0171: has to do anything with exhaust.

for P0171 what i will do? : simply clean the MAF sensor , take it off and spray it with electronics cleaner or brake cleaner. If this dosnt help? dirty fuel filter., checking all PCV hoses and vacuum.

 

This thread is what fixed my P0171 CEL: https://www.evolutionm.net/forums/ev...s-do-asap.html

 

So far so good for me. 50 miles in and no CEL after fixing spark plugs. I'm thinking they weren't overtightened though. I'm thinking they were dropped into the engine spark plug holes and that is what closed them up. Also just to be safe, I'm looking for the fuel pressure regulator hose that Tunerhead is talking about in my car. Do any of you have an 08 Lancer that knows where this hose is? I want to zip tie it up to be sure it won't give me any grief in the future.

 

any evo 8s with that code? Im still fighting with mine, i keep you guys updated.