i got an update for you guys,after observing my car for the longest time i took it to the guy that did my swap and i explained to him the symptoms,he said it sound like the o2 sensor so we did a little test he unplugged the connection of the o2 sensor and the car idled perfect,but the CEL is on which is normal he said coz we took out o2 sensor, he told me to drive it for couple days and see if it would still sputter and jerk,it idled better but still sputtered and jerks but not as bad as before, so it made us believe it's the o2 sensor,so he changed it at the same time i ask him to change my cat to a hi flow cat coz maybe that's what causing the problem too, he put a 2 1/4 magnaflow hi flow cat.after everything was installed car runs fine at that day,and then today i drove my car on the highway then i noticed that my car sputters and jerks around 4000-5000 rpm randomly and it idles low around 300-600 rpm but sometimes it idles fine then drop again, but even it idles low the motor seems to run finr it doesn't shake or vibrate that it's gonna stall.the car runs good when accelerating and i noticed one more thing if i step on the gas usually 3rd and 4th gear just holding it steady around 2500.2700 rpm the car will jerk a little bit like it bogs or something.this is what iv'e done,
1.spark plugs
2.spark plug wires
3.cap and rotor
4.fuel filter and fuel injection flush 2x (always runs fine for few days after flushing the injectors)and pulse test for the fuel injectors with good results.
5.ignition coil brand new
6.got the ignition timing checked
7.iacv cleaned
8.o2 sensor brand new
9.magnaflow hi flow cat
do you guys have anymore ideas what's up? please reply thanks.