might as well chime in sense i just fixed this issue , get a obd2 reader with live data. 1 it could be maf sensor is dirty , no idea what it should say at idle , if you need it tell me ill pull it in a day or so . 2. Fuel injector an how i found out i had fuel injector issue is my engine rumbles at idle randomly as hell . an i dont mean rpm icnreasing rumble i mean just rumble vibrations. could be clog / injecting to much. in my case clog threw it away put new ones on all 6 there only $30 for 8 , 6 pack of them was $40 ( kinda dumb) . 3. does your car seem louder ? possible exhuast leak ? 4. get a flash light that does not make it very hot such as led for saftey check under it for leaking gas run it for a few then check under psossible gas line leak cant hurt to do a visual check . 5. maybe but im doubtful its the fuel pump , this is like last resort replacement . 6. highly likely vacuum leak from a hose , turns out them vacuum lines control a heal of a lot of stuff on the engine from heater vents opening / closed to many others things. i suggest visual inspecting under hood vacuum lines an open glove box bend it down look under neth for holes in them . Report back what you find i can give you many other things to check cuz brother i was in the same boat i had ot check everyything before i found my issue ! mine was a cut o2 sensor wire along with a burned vacuum lines hose an a dirty maf . it did not stop tell i fixed them all reset the computer unpluged battary with wires together for 1 hour!