Crépine d'huile de l'électrovanne de désactivation obstruée

The fine filter in front of a cylinder deactivation solenoid, and the cheapest item on a list whose far end is a camshaft.

It is a different screen from the one in front of a camshaft oil control solenoid, though the two fail the same way and for the same reason. The camshaft screen serves variable valve timing; this one serves the lifters that switch a cylinder off. An engine with both has both, and cleaning one does not touch the other.

It blocks because it is doing its job. It catches what degraded oil leaves behind — varnish, carbon, and the debris of ordinary wear — and the passages it protects are small enough that a partial blockage is enough to slow actuation past the point the module will accept. That is why performance codes point here and circuit codes usually do not: the electrical side is fine, and the oil simply did not arrive fast enough.

A quote that starts at the lifters and skips this is worth questioning, because the screen is an afternoon and the lifters are an engine-out job on many V8s.