So the other day I'm driving along and my SES light came on. So I go to get it checked at autozone and the code they gave me was p0108.

The only thing I can tell that the car is doing wrong is that sometimes it won't downshift. It seems to do it when I've been driving for awhile already, or if I'm on the interstate going at higher speeds.

For example, I'll be cruising along in whatever gear I'm in, lets say 3rd. I'll go to accelerate and step on the gas but it wont downshift like it normally does and should. The car will just stay in whatever gear it's already in and shift up when it reaches the right shifting point. When I slow down, there are no problems shifting down or anything. It just doesn't want to downshift sometimes.

I guessed it to be something regarding a vacuum leak or something. The code said it could be that, the throttle body lose (not it, I checked it) the BARO or MAP defective, or the VAF or MAF sensors could be defective.

If you guys could help out that'd be awesome. Thanks.