280 lazy ides rough dies when puts in nutreal

[natemart94561]

I have a 280 that runs rough won't idle dies when I shift it into neutral. It seems like it want to run at speed with a 26 pitch prop but won't pull a 30 like it used to. Fuel pressure is good new plugs ql77cc. Water pressure is 15 lbs about 4000 rpm tps is at 801 I get a misfire on number one occasionaly. It just sounds like **** at idle. Changed filters. Coils are dry swapped ecu reeds are good compression is 140-145 across the board.seems like it won't go over mid 6000 rpm. One of the ecu' was in breakin mode and I thought that was gonna be it but didn't really fix it

[speedinstream]

Check tps

[capteliminator]

Have you ever had the injectors cleaned? Also check the air temp sensor, my 280 had similar symptoms and needed a new one.

[Dave Strong]

How many hours on the motor? Done a leak down test?

Dave

[natemart94561]

Ok leak down was with in 10%. Tps is at 801. The ddt says air temp sensor is good.

[PanRonnie]

you wrote you had a misfire
did you try swapping the coils?
could not read that
did you also try a fresch set of spark plug?

[natemart94561]

Ok so now I switched out the injectors and I got my idle to come back and seem smooth. I'm starting to think I got the water pressure sensor mixed up with one from a compleatly different carb motor. Does anyone know the correct part number for the water pressure sensor and it just seems lazy and lethargic still

[eli]

10 % leakdown across is getting tired

[mrcrsr]

also, is the map and fuel pressure barbs in the plenum clear? they get clogged and gummed up, and map sensor no longer gets an accurate reading. see if you can blow air thru the fittings. as said, 10% leakdown means it is kinda due for a rebuild. bad or wrong water pressure sensor usually will set a code and alarm, and bring on rpm limiting.