500 EFI with Whipple stage 2 blower kits.

Engine stumbles under light acceleration, around 1000-2200RPM, black smoke, smells like raw fuel. Proceed beyond 2200RPM, all is well and engine runs great.

Has some trouble idling at times, especially in gear.

IAC count stays at 140, does not change. Oher engine hovers at 25-50. IAC remote hose is also FULL of raw gas, not even sure how this is possible. My guess is maybe IAC is stuck closed?

Replaced bladder in the regulator thinking that could potentially be the issue but no dice.

I should also mention the oil smells like gas.

Any help is appreciated

Thanks!

Id pull the IAC on suspect engine leaving the wires plugged in and cycle the key on and off and see if it moves in and out

I'd pull the injectors,,1 or 2 may be leaking and if the engine is trying to stall,ecu cranks open the iac.

I should have mentioned, I just had the injectors tested and inspected. All passed. This was my first suspicion.

IMO the iac wouldn't be causing issues above idle rpm.

That setup runs a Map sensor? Did the hose fall off/crack/sensor go bad?

after you worked on the regulator?

Had a similar issue with my 700s. My throttles were a little off. So went through a bunch of diagnostics. Turned out to be a bad coil. Engine gave me no warning on vessel view which was perplexing. Check your coils

Unless modified the 500 EFI has a single coil,

This is true. The way this system is designed if the IAC is stuck closed, the injectors spray right at the inlet inside the blower for the IAC rremote hose, and would fill the hose wih gas.

I replaced the IAC and did a reset procedure, all seems ok now. IAC count would stay at 140 regardless of TPS before. Now it hovers between 0 and 25. I can hear it working when you give it quick throttle. Will water test later and report back.
MAP sensor and hose all look good.
I would agree that this would only affect idle condition, but I have seen weirder things happen.

No, Injectors were tested before I replaced the diaphragm in the regulator.