neon engine noise

02 neon sxt auto. when im at a stop and floor it. sounds like gnarled machine gun.. like the engine wants to go so bad...but is restricted. almost like tapping valves. im sure its not tho. so i replaced the plugs. pulled cyl 1 plug out...the wire was coverd in oil. cyl2&3 were fine cyl 4 was oil covered as well. all the plugs looked pretty good tho. anyways. i replaced them all. started back to my house. stopped and poured a whole can of sea foam into my tank (gas light was on) so i figured it would clean it out and burn good.. car ran like a champ. like a 4cyl on crack...lol but the next day. runs like crap again. same noise coming fromthe motor as before. the day i replaced plugs and put sea foam in it. i would floor it and smoke the tires.. but not now..... also while at speeds from 5-35 car wobbles real bad.. like a broke belt. couple months aog had the driver saide tie rod replaced. so i thought maybe it was the tie rod on pass side. but friend told me if it was tie rod. it would be at high speeds. but it only does this at low speeds. is it the tires? mechanic said tires were bad when i had the tie rod replaced few months ago... thanks