My 2002 Liberty 2.4 with 230 000 miles on it is having engine issues. Cold starts are rough. First few seconds it barely runs and sometimes I even have to press little on the accelerator to keep it running. After a few seconds it starts running perfectly fine. The main issue is loss of power below 2000 RPM. It runs fine only if accelerator is depressed just a little bit. Maybe after 1/4th it starts stalling and misfiring. Load has no effect and this happens even if the transmission is on neutral. Engine runs fine after RPMs rise over 2000. This started about a year ago and happened only when the engine was cold. Since then it has been getting worse and now happens also when the engine is warm. The check engine light is not glowing and there are no fault codes. I've found threads about similar problems on the internet but they are not so useful. Many times the final fix for the problem is not told and there are dozens of possible ways to solve the problem. Only thing I have learned is that this may be ignition-related. I've checked the first cylinder spark plug because it is the only one easily accessible. It looked fine but gap was a bit too large. I set it correct but there was no effect. I also measured the first spark plug wire and the resistance was correct according to the service manual. What should I do next? Should I just check the other spark plugs?