1998 V70 T5 2,3l Very high idle at start

[pjcat]

My IAC makes a similar noise. Doesn't sound good but it works.

I'm thinking a vacuum leak. Since you just did the PCV job maybe a vacuum line came off.

Will also check once more on this one. Thanks.

[cn90]

In most modern gasoline engine (post-carburetor era...):

- A vacuum leak usually causes misfires and stalling (lean mixture).

- When the engine revs up higher than normal, this happens because:
* stuck throttle plate
* bad ECT sending wrong signal ---> ECU sens out wrong output for injector.