Lexus SC check engine light air valve issue

Ugh, check engine lights are the worst! Is the engine running rough? Could be a vacuum leak somewhere, causing all sorts of problems with manifold pressure. Have you checked all the vacuum hoses around the throttle body?

A vacuum leak near the throttle body, potentially? Would that typically trigger the air valve diagnostic, or could it be masking a separate air valve issue?

It definitely could. Vacuum leaks are notorious for throwing off all kinds of sensors. But, honestly, with those symptoms and error codes, getting it properly diagnosed would be best. Could save you a headache in the long run!

I appreciated the input. It was indeed a faulty hose connection from the pump to the valve. Repair cost 175€ at my shop.