ecu reprograming? tranny not shifting correctly? Mass air flow sensor
 

I am totally lost on this one any suggestions would greatly be appreciated. I recieved a 2003 chevy silverado to drive back and forth to college and every since i got it shifted very firmly into 2nd gear. I think it might be getting better the more i drive compared to when i first got it 3 months ago. I was told to disconnect the battery for 30 minutes and that will set the tranny into a learning process to learn how i drive and learn the shift pionts from my style of driving. so i did that. the tranny did relearn stuff but it still shifted firmly into 2nd gear BUT now 2nd to 3rd gear shifts are are really light it, feathers in the gear it also does in 3rd to 4th gear change as well but feathers in a lot longer. a couple hundred miles later my my tranny shifted really weirdly and the check engine light came on. it said my mass air flow sensor. so i than replaced it. my old one looked just fine not dirty or broken at all. than a couple miles later the check engine light came back on same code. i started doing some research and found that i might need to get my ecu reprogramed. I never heard of reprograming the ecu so im not sure about that. Open to any suggestions thanks in advance.

try this. it worked for me. disconnect the neg. battery cable for 1 hour. reconnect it and turn your key to the on position... do not start it, but turn it like you are going to start it. let it stay on like this for 30 mins. then turn your key off and start the truck. let it idle for 5 mins and then drive it for about 10 to 20 miles. should learn your patterns and no check engine light. also check your ecm fuses in your under hood fuse/relay box.

ok. i will give it a try tomarrow. Thanks for the suggestion

it worked for me. disconnect the neg. battery cable for 1 hour. reconnect it and turn your key to the on position...