Toyota Repair: powerless 2000 echo, mass air flow sensor, mass air flow

Question
I just took our 2000 echo for a drive after my daughter told me there is a problem. The check engine light came on about 3 weeks ago. The code diagnosed was for lean mixture. I was told to use injector cleaner first...which I have. I disconnected the neg. battery cable to re-set check engine light. Now, when starting out to drive, the engine won't give higher throttle..let alone move the vehicle at any great rate of speed. It loped along at about 20 mph. After a few minutes, it seemed to get more power back and the car started to speed up. The shifting did not seem rough (automatic)  once it warmed up and there was no significant change to the engine sound. It turned off without any problems. I did rev the engine some before shutting it off...no problems. What should I check?

Answer
I would replace the MAF (mass air flow sensor) in the intake tube.
It gets dirty and cant meter the air properly.


You prob dont have a scan tool. If you do/did you would look for high fueel trim in the freeze data for ST and LT .
Short term would be over 10
Long term would be over 20
That would be the "official" way to confirm.

Mike