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Hello, I hope someone can help troubleshoot before the summer is over, our summers are short here in Massachusetts. I have a 2003 response lxi with a monsoon 335. Engine starts up ok. Idle is decent sounding. Moving forward, there is loss of power. Opening up throttle will only get up to about 2,000 rpms and 20 mph maximum. And it is slow getting there. When I rev it in neutral. It will go to high rpms, but when I pull back the throttle to neutral it sometimes stalls. The air intake gives a hissing sound more than normal when changing to forward, or throttle coming back down to neutral. here is what I’ve checked so far: fuel pressure is 40 at neutral and 48 when trying to move forward. Changed fuel filter. Put additives in fuel, star tron, stab il, sea foam. Changed MAP sensor, ITC sensor, water temp sensor. Unplugged oil pressure sensor (forward going to gauge) and pointing port side. Runs same with either disconnected. Oil pressure reads 20 when idle, goes to 40 when underway. Temperature gauge reads 160. Checked timing, it’s 20. Changed spark plugs, cap and rotor. A few years ago the alarm started sounding under the dash. Sounding all the time. The engine was running perfect and gauges were reading normal. So I disconnected the alarm. It ran for a few years after that running perfect. Until now.