Sputtering and popping and sounds like a bad 2 step around 1500 rpms

What's up TGC I haven't been on in awhile. The 8g been down for about 4 years so I decided to focus on getting her back on her feet. She was down because of a blown fuse which I had found out about 5 months later but she also needed valve seals and since I had other vehicles I said I would take time and replace the seals. Well that took me awhile (4 years lol) to do because I wasn't really giving her the attention she needed but now I'm ready to ride her again. So I got everything back together changed water pump and all the belts and got her running but I'm having a problem. She starts but sputiers and pops and when I give her some gas like about quater throttle it sounds like it's on a rev limiter around 1500 rpms. Then if I go further on the throttle it gets to about 2000 rpms and it sounds like it on a limiter and it sounds like it's gonna die then soon as the rpms drop back down to around 1000 it'll pick itself back up and go back to around 2000 and drop again all while my foot is about almost full throttle maybe 3/4 throttle. The temp hand will also go up a little when i hold the gas down and it's sputteeing and popping. Also it has a rough idle and believe I have a short in my wires for my obd2 connector under the dash. I hook up my scan tool and it won't connect but it will turn on and if I wiggle it the scan tool will shut off. Any help any suggestions any information will be appreciated thank you. I really miss this car it's been to long since I've driven it. Cars is a 2000 galant es 2.4l auto