New to this and clueless....engine issues!!

[Chazz]

I have a 2000 Challenger with twin 717's. Right engine works fine left engine not so much. It has been acting up since last fall. At first I though it might have been bad gas so I ran a new tank through it and put some Seafoam in with the new gas. Took it out earlier this spring and it ran okay for the most part, it would run erratically once in a while when going WOT, usually right after you went WOT from idle or slower speed. Now after I swapped plugs and cleaned the fuel filters the right engine runs like a champ and the left engine runs like crap. It won't get above 4500rpm. When at an idle, if you advance the throttle all the way, it will bog down, nearly die (usually does unless you drop the throttle) and then limp it's way up to 4500rpm. Both engines start up and run fine at an idle, even up to about 2000 to 3000 rpm. I don't even know where to begin. I would like to try some quicker/cheaper fixes before I send it to the shop for a tune up or major repairs. Also the boat pulls to one side a fair amount even when the engines are at the same rpm. Thanks in advance.

 

[ocod]

take carb off and clean it would be a start.
Seafoam in a two stroke may be a no no but if you ran through the tank of gas with it I would still take off carb and clean them.
Also, replace grey lines if you have them.