Check the hose clips for tightness and inspect the trunking for any cracks or splits and furthermore every the vacuum system, the little bore pipes and fittings for cracks and missing parts. The best exaggeration to locate a leak is to have the engine running and hot and after that spray lighter gas /propane or brake cleaner nearly each joint in turn. If the engine rev s going on you ve found your leak.
Its after that worth getting the fuel pressure checked as if this is low due to a blocked filter or faulty regulator or even a under the weather pump will all repercussion in insufficient fuel beast delivered to the engine. Might with be worth cleaning out the idle promptness rule motor / valve as these get clogged going on when carbon and some brake cleaner washed through helps free things off.
I don't have any check engine lights unless I unplug the MAF sensor. like the MAF is plugged in after that the car will stall unless I put my foot on the accelerator. There is then an intermittent popping sound coming at idle.