First and foremost i want to take a quick minute to thank everyone here for your knowledge. I browsed through many different threads trying to figure out how to go about fixing the P0171 (too lean bank 1) on my 04. What i kept on seeing was to pull out and clean the MAF (mass air flow) sensor. Well did that yesterday, cleared the code, and no light on today. Passed the emissions test today... (yeah i know, stupid Illinois with their goofy emissions tests,.. hate em, theyre worthless wastes of time!)

Anyways, Really simple though.

**First before anything you must use MAF cleaner spray ONLY! As others will leave a film, thus making your problem worse than it was to begin with. I spent about $6 on the spray.

*Im not sure if you have to or not but I disconnected my battery. (never can be too safe with electronics)

*Locate the MAF sensor. Its after the air box (filter) and right before the throttle body.

*Disconnect the electrical connector.

*Take of the two screws (You WILL need a T 20 torx security bit though for the 2)

*Remove

* (DO NOT TOUCH THE TWO VERY SMALL WIRES WITHIN THE SENSOR!)

*I held at a distance of about 8 - 10" and gave around 10 light spray bursts, then waited for any run off.. (was none.. stuff dries almost instantly) Then i hit it again with about 6 more light sprays.

*Replace.

*Reconnect electrical, and reconnect battery.

* DONE!

Much respect to those that i obtained this info from. Without that I would be still stumped on this issue. It worked for me. I just hope it works for other before they waste time and money on unneeded repairs. Thanks Everyone

 

glad to hear its fixed

 

Thanks for sharing your success story!! That's always good to hear a problem resolved!!

BTW - In the pic of the throttle body.... Is that your car? If so, what's the plate between the throttle body and UIM?

 

Glad to hear it, Matt! Hopefully it will stay gone. I've had a recurring P0171. Cleaning the MAF sensor was also my first step.

You have a very sharp looking Monte. I love that blue.

 

Looks like your basic TB spacer.

 

--no that not a pic of mine. i couldnt find my camera so i worked it the great ol american way... googled it. haha

 

-- thank you. and yes i really hope it stays gone as well.

 

I must say though. Without being in this forum i probably would have went and replaced the o2 sensor(s) without even knowing about doing the cleaning first. Saved me both time and money.. You guys are awesome!

 

Sadly after only 2 short months, my car is shooting me the same p0171 code. (Too lean, bank 1)

Which route shall I use this time? Would it serve me any good to RE-clean the MAF sensor? And as Iknow my car has 2 o2 sensors. 1 upstream and 1 downstream. Which of the two (or both) are in Bank 1? I've noticed my gas not lasting as long as it should either. Would this be due in part of the "too lean" issue? Car was tuned up less than a year ago

In going to check, and clean the sensor again tomorow. Along with checking vaccuum lines. Anything thing else that should be checked?

Sorry so many questions, but I want to get this problem resolved, and I know I'm in the right place for that to happen. Thanks in advance!

 

That would be the upstream sensor, connects to manifolds.
You get real crappy MPG's, and a funky smell.