P0171 what to try..

well that's good but if it happens again .. you know what options you have

 

Yea, we will see if it stays off. I’m kinda doubting it.

 

Mine will do that. Then comes back. The other day it was off for the whole day. It returned the next morning.

 

I mean it's like 10 bucks for the pack of foulers , just time and some wrenching to fix it after that... might need a torch to burn it out too

 

So far it hasn’t come back.

 

well that's great then

 

Spoke too soon lol. It’s baaaaack.

 

lol u know what has to be done

 

Finally fixed mine for good. Paid a local shop to diagnose it, this is what they found. Water temperature sensor was reading 50˚ lower than actual water temperature AND the Mass Airflow sensor was only reading 3.5 gm/s at idle when it should be somewhere around 7. Not sure about that measurement, just going off of what they told me. This caused the ECU to call for a lean mixture which in turn caused the code. I can't fully wrap my mind around that right now, but no code after 300 miles of driving makes me happy. Replaced the water temp sensor ($40) and MAF sensor ($77 Amazon *Denso)

Now we get to move on to fixing the stuff that it actually needs, brakes, valve cover gaskets, timing belt.

 

sounds like you found a shop that truley knows what they are doing, that is good news.

All of the sensors are part of a system, inputs are measured... air temp, air volume, water temp, rpm etc and from that fuel delivered via the injectors is controlled, spark adjusted, etc. A/F sensors, O2 sensors measure the result of the combustion process and compare it to know good values. If the values are out of range, adjustments are made, if the range of adjustments is beyond what can be adjusted, the CEL is illuminated.