2.3L ('02-'11) Ok - I have a plan in place now ( If you've ever seen the movie, Momento about a guy who has to write everything down)

[Garth Libre]

I have a 2010 2.3 Liter Ranger (manual transmission). It threw a code for too lean. So I know the problem is likely the two O2 sensors and/or the Mass Air Flow Sensor. The car has well over 100,000 miles so technically all these sensors have lived a complete service life. None of these parts are very expensive - it's all about the time and the labor saved if I had to pay someone (plus the markup for the parts).

Parts:
O2 sensor socket from Amazon $5.89
2 O2 sensors $18.50 each from Amazon
Mass Air Flow sensor cleaner from Walmart $6.97

The mass air flow sensor is NOT the same thing as the O2 sensor as the mass air flow sensor is near the intake and supposedly just cleaning it can be all that is required.


These type of jobs are not what I used to think of as Auto Mechanics as they are more technical and belong the realm of electronic, modern cars (not the old fashioned carburetor stuff I grew up with). Any help from guys who have dealt with this before.

 

[Brain75]

I'd start before you spend a single penny in getting it to throw the code again and then sharing the code... P0171+P0174 is like 90% of the time air leak (intake gasket or vacuum or pcv - too much air getting in that is not metered). P0174 stand alone is kinda mixed bag - as you got it MAF, air leak, O2 sensor, etc.

Two big issues
1) "new" parts are just plain crap on the aftermarket now - so throwing a bunch of parts at it first will tend to make it worse
2) without the exact code asking for help all we can do is give you a bunch of random directions to aim at and hope.... dissecting it scientifically with good data and diagnosis is not only faster but cheaper (no wasted money on 4 different O2 sensors trying to get a good one when it wasn't the O2 sensor to begin with)

 

[JoshT]

What was the actual code.

I'm not going to say that 02 sensor is not your problem, but usually the O2 does not cause a lean condition, just reports it. If the O2 sensor is the cause it is only the front sensor. The rear sensor is just there to verify that the cat coverter is doing its job.

MAF is certainly a possibility, and cleaning it can't hurt. A very likely cause for a lean condition is a vacuum leak. That is any leak that exists between the MAF and cylinder. That is unmetered air that is getting in and not accounted for in fueling.

 

[Brain75]

I'm also going to throw out that engine-codes.com is one of the best OBD2 listings as far as which steps and what order...

 

[SenorNoob]

Gonna throw out that 2010 is about the right age for vacuum lines to be leaking...

Also, I've only seen one bad MAF. The truck had codes for overvoltage and undervoltage at the same time. I replaced it with a junkyard part and drove it for 2 years.

Replacing O2 sensors usually isn't as easy as it sounds. They like to stick. I bought the good socket and brought enough cheater pipe to the fight to pick up my pickup and still wasn't able to get mine loose. I ended up putting a new y-pipe in. I had installed that sensor myself. (10 years prior) They do need changing sometimes tho.

 

[Blmpkn]

If the o2s were bad they'd be throwing codes that say they're bad.. not throwing the codes you have.

Circuit malfunction codes, voltage issue codes, slow/no response codes would indicate bad sensors..

The codes you're getting seem to say that they're working just fine.. and letting you know the truck is experiencing a lean condition..

Leave em for now, and once they DO need replacement.. don't use 18$ Amazon specials. Find yourself some motorcraft pieces or NTK.