My Avensis is s petrol auto. And has a very erratic idle. The dealer assured me it was the throttle body which they replaced. But the problem persists, the idling normalizes when the climate control is switched off and is worse when operating hot. What else can this be as I am spending a lot of money on something that they cannot seem to put their finger on the problem. Can you give some advice?
I believe it is equipped with VVT, have its solenoid checked, clean it and its port of any slugde if any found retest. When problem occurs, lightly tap the solenoid with a rod or small mallet, do not use force. If the idling stabilizes suddenly, the solenoid is bad and sticking intermittently, which might not trigger any trouble codes.
If VVT solenoid is not the cause, check the valve clearance and adjust if necessary.
Was the throttle body replaced by the dealer with a new part complete with IAC?