Help!!

[01kia_rio]

Alright, i am new to the forum and really don't even know if this is the right place to post this, but i really need your guys' help as i am fairly new to kia/hyundai as well. but i have an 01 rio and i have a major problem. My car is bucking terribly bad, and it takes forever to reach its speed and its top speed right now is only 60 km/h now i have replaced all the filters, plugs, new wires, new coil etc. and my problem still isn't cured, if i rev the car up to about 4 grand it bogs out and wheni let out the gas it bogs RIGHT out and will stall, it won't rev aboce 4, and runs VERY rough between 1000 and 2000 rpmbut between the two it runs good. I can't seem, to figure out what this is. the check engine light is on sometimes, and when i had it checked it was saying the maf was bad, so i replaced it. and it hasn't done anything, so please, i need ANY input on what this may be, i need this car working again asap.
Thanks,
Colton

P.S. did i mention that the odd time it will work fine like there is nothing wrong with it?

[ereeves116]

does it smell like it is running rich? not sure if it's the same but my ford does the same thing. does yours idle rough? it might be the IAC (idle actuator control) and maybe check your fuel line, one of your injectors could be dumping too much fuel causing one of he cylinders to bog? or the whole fuel delivery system is sketchy and bogs the car down at certain RPM ranges. i'm thinking just based on my experience that it could be a fuel problem. any issues with fuel efficiency?

[01kia_rio]

actually i noticed it did smell a little rich but that could just be me, cause my fuel system is working good. so i don't know. i might have it checked again when i bring it into workkk again this or next week

[01kia_rio]

heres a short video of what it is doing, take note that i am easing the gas on the whole time in this video as it bogs down.

YouTube - rio