01 XJ8 Air Assist Control Valve

My 01 X308 keeps tossing a code saying the AACV has failed. I reset the code and it drives fine and no lights when warm . When cold it throws the code in about a mile. Trying to source the Denso valve so far no luck. Any thoughts from the brain trust on solutions. The shop said the resistance in the line was low, would adding a small value resistor keep the light from coming on??
Naturally it’s on the car I want to sell.