Check the hose clips for tightness and examine the trunking for any cracks or splits and plus all the vacuum system, the little bore pipes and fittings for cracks and missing parts. The best showing off to locate a leak is to have the engine paperwork and hot and subsequently vaporizer lighter gas /propane or brake cleaner just about each joint in turn. If the engine rev s happening you ve found your leak.
Thanks for your response. I just checked what you mentioned, that I hadn't already checked, except fuel pressure.Let me tell you a little more very nearly the trouble history. It currently has a master tech official idle let breathe run valve and tps installed. without moving anything, the last (used) ecu and my original, would run in the car without this symptom.
next I begin the car, the engine surges in the works amongst 1200 and 2000 rpm back and forth. I misused the IAC and the TPS like no change in symptoms. I have noticed that several Lexus SC's have this thesame issue. Prior to this I would have to accustom yourself the idle readiness screw to humiliate the rpm and it would keep for a while. Now, the engine is permanently surging to the tapering off where I cannot drive it for clock radio of damage to the steer train. Any experienced solution?