Rough idle

[rav4t180d-cat]

Hello novice to forums but looking for advice to anyone that may have had a similar issue regarding the t180 rav4. It runs well 140k miles poor fuel consumption recent injectors and rail. When i come from a run when vehicle warmed up and I come to idle around 800rpm you can here rpm slightly slowly drop then suddenly but briefly bounce up to around 1000 rpm then come down to 800 again and will do this inconsistently. No fault codes useing my autel scanner only anomaly I can see is fuel pressure erratic and when it bucks the fuel pressure has dropped down to 22000kpa ish and target pressure 32000kpa at idle going off my head which when running is up 38000 plus kpa bouncing up and down all over the place. Its also had a new genuine scv valve. Starts on the button goes well occasionally hesitant to go from a stop. Fuel filter about 3000 miles ago no coolant loss ever and oil never drops. 5th injector to the dcat system been blocked no improvement to fuel economy but has stoped the embarrassment random clouds of smoke. My thinking is maybe I'm sucking air into the fuel system which is more evident during idle air compresses in the fuel rail and drops pressure momentarily???? Is there a known area for these to suck air fuel filter housing? Thanks for any input and sorry for the long winded description.