Any idea what caused this? Car started, SAI whine came on like usual. The SAI pump turned off after about a minute as it normally did in the past. After the car warmed up (maybe ten minutes later) at a stop light, the SAI turned on again, then I got a CEL. Isn't the SAI only used during cold starts? Mine has been turning on occasionally after the car's been warmed up but hasn't thrown any CELs.

Last time it was a leaky vacuum hose, but couldn't find any visual evidence of leaky hoses.

Thanks in advance

Should only be coming on before the cat gets up to temp, far as I know. Did you pull any codes?

My CEL comes on 5-6 times per month with the P0411 code. I keep a $50 code reader from autozone in my glove box, so I just reset it and keep moving. I've looked for the leak but can't find it, so I'll not worry too much about it since it is intermittent.

I had the same engine code and I ended up replacing the SAI. The connections coming out of the SAI were rotted and broken so I assumed that water got into it. You shouldn't actually hear it come on. If you hear a turbine sound, that means its dying.

what kind of connections? the air flex hoses or the electrical?

The air hoses. The power connection should be fine. Unless somehow those got damaged.

I can hear the SAI EVERY morning. Vacuum cleaner, jet sound. I'll replace it next month or so along with some vacuum lines I've yet to replace. Thanks for the input. Really appreciated!

Yup that's the sign that the pump is shot.

Honestly, you should go under there and just unplug it. If you have the same situation I had, then it is literally pointless for it to even be wasting power and creating an annoying sound.

Yeah mine did the same thing, so I ripped out the SAI pump, combi valve and all of the associated plumbing and added an Integrated Engineering blockoff plate to cover the hole in the cylinder head. Then I paid to have SAI readiness coded on in my ECU. Then I failed three state safety inspections and now I have to buy all that stuff back and replace it...