I have C11 Cat that has low power....codes for IVA unresponsive on #6. Swapped solenoids, still on #6. Moved IVA assembly from #5 & 6 to #1 & 2. Adjusted valves, injectors, and IVA. Problem moves to #2. Replaced IVA assembly with Cat Reman unit. Still runs bad... Login to read more.