Check the hose clips for tightness and examine the trunking for any cracks or splits and furthermore all the vacuum system, the little bore pipes and fittings for cracks and missing parts. The best showing off to find a leak is to have the engine government and warm and later vaporizer lighter gas /propane or brake cleaner something like each joint in turn. If the engine rev s in the works you ve found your leak.
Might next be worth checking the wiring and connector to the airflow meter for any signs of corrosion or damage. you can get a quick fault locate if you unplug the meter and direct the engine without it. if the engine condition is the similar later chances are the meter or the membership to it is faulty. Its after that worth cleaning the MAF sensor wires, as they can acquire coated with dirt higher than epoch which subsequently offsets the reading. Use some retrieve cleaner or brake cleaner to spray onto the wires to remove the dirt on no account touch the wires taking into account anything as they are utterly fragile
taking into account I begin the car, the engine surges in the works together with 1200 and 2000 rpm urge on and forth. I misrepresented the IAC and the TPS considering no change in symptoms. I have noticed that several Lexus SC's have this same issue. Prior to this I would have to get used to the idle enthusiasm screw to humiliate the rpm and it would maintain for a while. Now, the engine is until the end of time surging to the tapering off where I cannot steer it for agitation of broken to the steer train. Any experienced solution?