1992 225 intermittent acceleration

[pjw]

I'm looking for help on a '92 225. It has 400 hours on it and is kept in good shape. It idles fine, acceleration with torque starts to bog down with a pinging sound and sometimes it dies. Once I get past that, full throttle is fine. I never had an issue until the ethanol came along. What I am understanding is that I should rebuild my carbs because the mid-range jets are probably clogged. A mechanic showed me several carbourator bowls that he had in the shop that were actually eaten away from the ethanol.
Do you have any info or suggestions?
Thank you

[boats.net]

Probably need to clean carbs and check fuel pumps.

[pjw]

I just replaced the fuel pumps and it didn't help, even though when I disassembled the old ones and they were beat. I'm still having acceleration problems under load between 1000 and 2000 RPM's. Everything else is great. I guess it's time to disassemble the carbs. Do you know what the throttle sensor on the 225's actually do? It must have something to do with the choke. Let me know.
Thanks