P0171 and P0174

[Mbknut]

Does anyone have a good idea where to start in tying to trace this indicated lean condition?
I have a 2002 Explorer Sport Trac, and sometimes I just get bank 1 and 2 too lean, sometimes the lean code is for both oxygen sensors (new Bosch, just replaced), and sometimes tha adaptive device at max limit comes on. Sometimes I only get 1 or 2 codes but sometimes all 5 come. I have a good code reader. but I need some help!

 

[SuperProtege5]

I had the same code pop up about it running too lean in banks 1 and 2. CEL came on about two weeks ago, still on. Guy at autozone told me to check the MAF sensor. I cleaned the air filter so that wasn't it. Also, now whenever I'm sitting at a light, the car wants to stutter and rock so I have to put it in neutral to get it to stop then put it back in OD whenever the light turns.

 

[performancenut]

MAF cleaning procedure may work. Both banks are affected, so it is likely an issue related to the air/fuel intake process.

 

[spindlecone]

On the 02 and up SOHC V6, the codes you report are almost always a vac, leak.
Could be your intake O-rings.
The most common source is a cracked hose where it enters the front of the intake.
Ck the rubber Elbow ( the large one in the pic)It comes from the PVC valve on the backside of the drivers side valve cover.
They crack on the bottom of the elbow, good luck.

 

[rd_turbo]

I had the same code pop up about it running too lean in banks 1 and 2. CEL came on about two weeks ago, still on. Guy at autozone told me to check the MAF sensor. I cleaned the air filter so that wasn't it. Also, now whenever I'm sitting at a light, the car wants to stutter and rock so I have to put it in neutral to get it to stop then put it back in OD whenever the light turns.

I noticed your username makes reference to Protege5. If you own a Protege and you ever get P0171 check your intake gasket for splits resulting in vacuum leaks. I went through hell trying to find the cause on my wife's Protege earlier this year and it ended up being an intake gasket that had cracked and was partially sucked into the engine. Cleaning the MAF sensor doesn't normally fix this issue although a small number of people have had some success on other cars.

 

[fljmruiz]

p0171,p0171

Does anyone have a good idea where to start in tying to trace this indicated lean condition?
I have a 2002 Explorer Sport Trac, and sometimes I just get bank 1 and 2 too lean, sometimes the lean code is for both oxygen sensors (new Bosch, just replaced), and sometimes tha adaptive device at max limit comes on. Sometimes I only get 1 or 2 codes but sometimes all 5 come. I have a good code reader. but I need some help!

This is George:

Check the pcv, vacuum hoses for crack.