Hello my name is Branson. I drive a 2002 Dodge Neon SXT. It has the 2.0L SOHC and is 5-speed manual. I wanted to add a little power to my every day driver but keep the reliability. Boy did I mess up lol I have recently installed a cold air intake, outside of throttle body pipe and cone filter into fender. I have installed a long tube exhaust manifold, cat and muffler deleted. After those "mods" I got an engine light for my O2 sensors. I bought sparkplug nonfoulers and drilled it out and gave both the top and bottom O2 sensor spacing. The engine light went off, and the car ran fine for a couple days. Then threw an engine misfire code, so I replaced the ignition coil, plugs, and wires. The engine light went off for a couple days again. Then another engine light for my TPS. I also replaced the throttle position sensor, engine light went off. The car has ran fine with extra power all through rpm range for the last 3 months. The car has 182,000 miles. Now my issue is this. Last weekend I was driving home on the interstate, about an hour drive. Doing between 70-80mph, nothing excessive. About 45 minutes into my drive I heard a small pop from the front, and felt a small loss of power under my foot, but barely noticeable. Then a small ticking noise began. In the last 15 minutes of the drive once I got onto the backroads it slowly progressed, but never was really bad or loud. Once home I turned off the car and checked my oil, and the level was barely below the full mark (assuming I had checked it a little fast and oil was still up top). Oil level was okay, antifreeze level was fine. Next day I drained the oil (5w-30) and replaced it with (10w-30), and changed the oil filter. After starting with 10w-30, the ticking noise still exists but is a little quieter. I then disconnected the intake at the throttle body, put my car in neutral with ebrake on, set a stone on my gas pedal and held it at 2000 rpm, I sprayed a whole can of carb cleaner into the intake to try and deoxidize the valves, thinking why not? It quieted the ticking even a little more but is still noticeable. Car is very sluggish in low rpm range of every gear. The ticking seems to be coming from the front, passenger side top of engine (cylinder 1). This had me stumped. I then removed the valve cover and visually inspected the rockers arms, but it isn't easy to see the valve springs or much of anything else. Without removing the head, where do I go from here? I am editing this a few days later, as now my check engine light is on, and I am throwing a code P1494 for my Leak detection pump pressure switch, car is running even worse. Editing again. I have replaced the leak detection pump connector as the wires were corroded and broken, and car now runs good. Still have ticking noise from engine bay, and check engine light.