OBDII code

[EBStang05]

I have a 2005 v6 Mustang. Only mods are CAI and Exhaust. Anyone have a problem with a P0171 System Too Lean (Bank 1) code? There are so many possibilities that can cause a lean code. Has anyone else had this problem or can anyone lead me in the right direction. I have not found any vacuum leaks and i have also cleaned the MAF sensor. The car only has 56,000 miles on it. Anyone have any ideas?

 

[The Fang]

Do you have a tuner? If so try returning to stock and see if it still does it.

 

[EBStang05]

No Tuner. Sad part is I work at a Repair shop and none of the mechanics seem to know..

 

[ccdguy]

Had the same thing after installing a "no tune necessary" CAI from AFE... No vaccum leaks either. Pulled same codes 0171 and 0174 or 3.. Can't remember. Anyway, your CAI is definitely making your Stang run lean. No such thing as "no tune" CAI. Each CAI will deliver way more air than your stock airbox. You will need to get a custom tune to allow the ECU to manage the air/fuel properly. You will either have to get it dyno tuned... (Expensive) or get an XCal2 or 3, or Diablo, etc tuner and a tune to support your mods.... Do something quickly as you do not want to run lean for long, if at all. One of the worst conditions to run your pony under. Better to be rich than lean. Anyway.. Definitely caused by your CAI delivering more air and the fuel delivery stayed the same. You are running dangerously lean if your ECU is pulling codes. Hope this helps ! Best of luck !

 

[hotcobra03]

I would just change them.i have bbk lts with no cats all o2s on .but thats me are anyother codes present?

 

[EBStang05]

There are no other codes present. I've had the CAI on for approx 40,000 miles and this is the first time a code has been set. I changed the Bank 1 upstream O2 sensor today just didn't have time to drive it and see if the light stayed off. So i'm not sure if the problem is totally fixed. Is there anything I can do to run richer? I run mid grade or 89 octane in it. Does this hurt/help?

 

[hotcobra03]

Po171 is caused by unmetered air. Ck air in to engine ,air thur motor and air that exits engine.pcv?evap vac?egr?

 

[EBStang05]

Do you think I need to have the car tuned since I have the CAI on there? Will the CAI just cause the car to run lean without the tune?

 

[hotcobra03]

That i cant honestly answer. I dont think so as to before maf.maf can cause code but would noticable with driving issues.i pulled my vacuum harness and found 3 bad hoses.on an 03.any tiny air leak.use a stethescope to listen it finds things you cant pin point.

 

[EBStang05]

O2 sensor did not fix. It seems odd that since i've had the CAI on for 40k miles that it would just now start throwing a lean code.. I guess the only way to tell is to get the tuner and find out? Anyone else have any suggestions?

 

[EBStang05]

ongoing problem

Bought the DiabloSport Tuner.... Tuned the car to the 93 octane predator.. and 50 miles later the light comes back on with p0171 and p0174... Tried replacing fuel filter which was dirty and didn't fix problem? Any ideas...

 

[hotcobra03]

With predator go into real time data and c what your stuff is reading .its a long story pm me if u need help

 

[hotcobra03]

Fwiw .his car is fixed. What was found was his air filter was pushed on to far . Air flow im assuming?