Our 99 GS300 has 160,xxx.
So we were going on an hour ride to edgewood and we started going up sedillo hill, and the RPM's started moving all over the place, but the funny thing is, the speed went from 75 all the way down to 40,. no matter how hard it tried to haul up the hill, we just went slower, and slower. We reached the top and it speed up and became regular again. So we took it into pep boys and they said it was the MAF. (CEL was on and that was the code it threw) So they replaced it. Same exact problem never went away. So we took it back in to pep boys, and they said it was the MAF, the one they had put in was faulty. So they replaced it. It worked for a couple minutes but than, CEL popped on again, and the problem intermittently happens now. We took it back in to pep boys and they replaced the O2 sensor(s)? as well. Same problem, but very slight. Any ideas what this invader could be?
Also almost every cold start, it takes about 5 seconds to start. We will replace the spark plugs soon.
Any ideas?

Thank you!

 

Whats the code?