P2071

P2071 is the mirror twin of P2070 — the Intake Manifold Tuning Valve is stuck CLOSED, meaning the long-runner path is permanently engaged and you can't get full air to the cylinders at high RPM. Symptom set is the opposite of P2070: the car feels fine at low RPM and falls flat above 4,000, fuel economy may actually look okay at light load, and the ECU sets the code when the feedback position stays at the closed-end stop while the command is asking for open. Cheapest-first ladder is identical to P2070: unplug the actuator, look for contamination, free the flap by hand with the engine off, clean the plenum, and verify the linkage clip is still on the shaft. Live-data check: command the IMTV through its full sweep with a bidirectional scan tool and watch stepper-motor current — healthy is 0.3-1.5A through the sweep; spike above 2A at one position means the flap is bound at that point. Confirm 5V reference, ground, and signal at the connector before swapping the actuator. Expensive-misdiagnosis caveat: a broken vacuum line on vacuum-actuated systems (Honda K-series, older Mazda) looks identical electrically to a failed actuator — smoke-test the intake vacuum tree before condemning anything that costs more than $50, and never quote the full intake manifold until you've verified the flap itself is the broken piece and not the linkage or actuator bolted to it.

Vehicle-specific patterns: 2005-2012 Ford 3.0 Duratec (Escape, Fusion, Taurus, Mariner) throws P2071 from the same IMRC actuator failure mode as P2070 but stuck the other direction — same $40-120 actuator, same 1.5-2.5 hr labor. 2008-2015 GM 3.6L LFX/LLT throws P2071 when the flap drops off its pivot and lodges in the closed position; the noise from a dropped flap is a giveaway. 2010-2014 Hyundai/Kia Theta II 2.4L (Sonata, Optima, Sorento) throws P2071 from carbon binding on the VIS flap, especially on GDI engines without port-injection wash. 2003-2013 Mazda3/6/CX-7 with the MZR 2.0/2.3 throws P2071 when the VTCS shutter shaft seizes from carbon and the actuator strips its plastic gear trying to move it. 2006-2011 Honda K20/K24 throws P2071 from a failed IMRC vacuum solenoid or a kinked vacuum line — Honda's design is biased to fail closed, so P2071 is more common than P2070 on the K-series. Estimated repair: $120 to $950.