2000 toyota tacoma code p0171

i just cleaned maf sensor, inspec all vacuum lines, sprayed brake cleaner all around intake manifold and vacuum lines, cleared code, but return again and again any clue will be apreciate, tank you in advance.

 

Turned out to be a hidden vacuum leak for me, check all your connections carefully. Took 2 different shops to figure it out on mine. An exhaust leak can also throw this code but vacuum leaks are most common.

 

Could also be a faulty O2 or a/f sensor

 

If your MAF is absolutely clean and there's no vacuum leak, it's a bad A/F/ sensor. I've had to clean the MAF before and it took almost half a can cleaning it 2-3 times to get rid of that code. Not long after that, the same code popped up and cleaning the MAF didn't do anything. I ended up replacing the upstream A/F sensor and the truck was happy again.