Check the hose clips for tightness and examine the trunking for any cracks or splits and as a consequence every the vacuum system, the small bore pipes and fittings for cracks and missing parts. The best quirk to find a leak is to have the engine meting out and warm and subsequently spray can lighter gas /propane or brake cleaner as regards each joint in turn. If the engine rev s up you ve found your leak.
Its then worth getting the fuel pressure checked as if this is low due to a blocked filter or faulty regulator or even a below par pump will every repercussion in insufficient fuel innate delivered to the engine. Might plus be worth cleaning out the idle readiness govern motor / valve as these get clogged occurring past carbon and some brake cleaner washed through helps release things off.
I don't have any check engine lights unless I unplug the MAF sensor. in imitation of the MAF is plugged in then the car will stall unless I put my foot on the accelerator. There is after that an intermittent popping unassailable coming at idle.