i think same happened to me,
i keep my car tank almost full of petrol, but normally drice on cng, bas kabhi kabhi mazay lene k liye petrol ya phir long route pe thora petrol thori cng.
for the last few days, my car is not performing well on petrol, ziada rpm pe thori deir k liye petrol ruk jata, phir dubara aa jata.
but yesterday, chalte chalte gas khatam hui to gari ne petrol pe chalne se inkaar ker dia
i got its fuel filter cleaned, but ziada farq ni para.
workshop gai to they said k pump khol k saaf kerein ge, aur sath me poora tank bhi, cz aj kal ka petrol ziada arsa guzar jae to yehi haal kerta he tank ka
now, InshALLAH on weekend, i will get the tank and pump cleaned up.