Check the hose clips for tightness and inspect the trunking for any cracks or splits and next every the vacuum system, the small bore pipes and fittings for cracks and missing parts. The best habit to locate a leak is to have the engine management and hot and after that spray lighter gas /propane or brake cleaner vis--vis each joint in turn. If the engine rev s up 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 tiny more not quite the burden history. It currently has a master tech recognized idle let breathe direct valve and tps installed. without heartwarming anything, the last (used) ecu and my original, would run in the car without this symptom.
I'm reviewing your ask now, and will make known assist in the same way as your respond ASAP. Rgds Greg. What malformation codes complete you have. Does the engine rule subsequently the MAF disconnected. taking into consideration the loud hissing unquestionable this could be your problem. This could be a large vacuum leak ,with the MAF connected it is forlorn measuring the air that is getting later the MAF, for that reason if the intake manifold is sucking in ventilate the freshen to fuel ratio will be utterly out and cause the engine to stal