My 2013 Rinker 290 MerCruiser 8.2 Mag will not make full power. Won't get on plane and only does about 15-20 mph at WOT and 4000 rmp. I have changed the cool fuel filters, both fuel pumps, fuel regulator, spark plugs twice, spark plug wires, both coil packs, MAT, PCV valve, taken out and cleaned the fuel injections, checked the anti-siphon valve. Engine compression is 139 - 145. Fuel rail pressure is right around 42 psi from start to WOT. I ran it on a different fuel source. Checked back pressure (less than 1 psi). No faults on Diacom. I found an alternator problem. I noticed the battery voltage was low while out on the lake. Found the alternator was not charging. After changing the alternator still had the same problem. Then found the multi battery isolator bad. I jumped around it and alternator works good now. Took it out and still no help. Still can't make full power. Engine runs good but is hard to start. I turn the key on and let the fuel pump run a few seconds, then crank it for 10 seconds with no start. Crank again with no start. Turn the key off and back on. Cranks about 3 seconds and fires right up. This happens every time I try to start it. Except if I try to restart it right after I shut it down, it starts right up. The timing jumps around at idle but is steady at higher RPM's.
I got a spark tester and a new timing light. While staring the first time I had no spark with no start. Key off and back on and I had spark and it started in about 2 seconds. I changed the crankshaft sensor. Timing was still jumping around at idle by 5-7 degrees. At 2000 rpm by 2-3 degrees and it was rock steady at 2800 rpm. I did a coil test and they all sparked on the test. Some seamed to have a bit weaker spark than others but they did all spark. Took it out and it was still lacked power. Tried propane in the intake and had no change at all at WOT. I changed the camshaft sensor with no help. Still no spark on start up. Key off and back on starts in 2 seconds. Timing still jumping and idle and lack of power at WOT. Sent the ECM to have it tested and UPS lost it. Bought a new ECM and no help. Any ideas?
I got a spark tester and a new timing light. While staring the first time I had no spark with no start. Key off and back on and I had spark and it started in about 2 seconds. I changed the crankshaft sensor. Timing was still jumping around at idle by 5-7 degrees. At 2000 rpm by 2-3 degrees and it was rock steady at 2800 rpm. I did a coil test and they all sparked on the test. Some seamed to have a bit weaker spark than others but they did all spark. Took it out and it was still lacked power. Tried propane in the intake and had no change at all at WOT. I changed the camshaft sensor with no help. Still no spark on start up. Key off and back on starts in 2 seconds. Timing still jumping and idle and lack of power at WOT. Sent the ECM to have it tested and UPS lost it. Bought a new ECM and no help. Any ideas?
