So the CEL light came on the other day. Checked the ODB code and it is a P0171 code. I then figured the MAF needed to be cleaned so I did this and reset the CEL and thought that everything was fine. Well after 50 miles CEL came back on. So I then decided to unplug the MAF and see how it is running and it runs horrible. Does this sound like I have an 02 sensor problem? If so does anyone have any schematics of replacing them? Thank you for your time.

 

Check for vacuum leaks.

 

id hook up a scanner and watch your fuel trim numbers while you spray carb cleaner a lil at a time around your intake where it bolts to the head.. if it is running lean at all times itll show 10 to 15% positive and then when you spray where you have a vacuum leak your trims will go negative momentarily where the car is trying to lean out the rich mixture.. and id try to do this on a cold engine because some of the smallest leaks will seal up when the engine gets to op temps.. how warm was the ect in your freeze frame data when the code set??

 

Thank you for the help. I found a cracked hose that was very hard to find.

 

Ok so I read the last few posts cuz this actually happened to my car the last couple days.. I've checked the main hoses that I can see and what not and I cleaned the MAF last night and still on and what not. I'm not the most knowledgable about the engine and what not.. Is there any way I can test that when I don't have a scanner and I really don't know where to spray the carb cleaner? Sorry I'm such a noob, but I try and learn as I go... If you could explain or show pics that would be helpful!

 

My mechanic has a smoke generator. Sergey uses it to find vacuum
leaks. He's just north of NJ in Rockland County NY.

www.edge-motors.com