رواسب كربونية تمنع إغلاق الصفيحة تمامًا

Carbon built up in the throttle bore at the plate's closed position, holding it fractionally open. That is exactly the range idle is controlled in, so a small deposit has a disproportionate effect.

The module compensates until it runs out of authority, then reports that it cannot achieve the commanded position — so the code names the actuator while the fault is a deposit. The idle is high and hunting, worst when cold. Cleaning is the repair, with two conditions: use only what the manufacturer permits, since many bores are coated and solvent removes it, and carry out the relearn afterwards — the module has adapted to the old closed position over years, and removing the carbon moves it. Skipping the relearn sets fresh codes on a throttle body just cleaned correctly.