Well first off. There is only one bank which would be all 4 cylinders. Second. Autozone more than likely does not carry IMRC's. And third, IMRC is short for intake manifold runner control. The intake manifold has two intake ports per cylinder. They are a butterfly type valve similar to a throttle plate. The IMRCs remain closed under a certain rpm for optimum torque and low end power. Once the engine reaches the determined rpm these imrcs via an electric module will open allowing air flow through both ports resulting in better power up high. You will either have to pull the intake manifold off or pour a small amount of seafoam into the intake manifold to free the runners. Or more simply reach on the rear of the intake manifold (if you can reach it) and try twising the imrc plate drive by hand to free them.(dont be too rough with them because if they're actually stuck because of carbon build up, you will break the rod and be in trouble) It could also be a fault within the imrc module or circuitry.
Last edited by 93mk8; 10-24-2009 at 08:20 AM.