V40 T4 - slow to start sometimes

[nutzu]

i will post here iven if is an old thread

i have some similar problems with my volvo t4 '99.

sometimes it starts hard ( not a pattern here) the car can sit 2 days and will start fine. for example yesterday i started it in 2-3 hours interval after a road trip and the car started hard ( after 2-3 seconds) if i give it some gas, will start right away. this morning started just fine after 1 night of sitting.

i replaced all filters , oil, belts( before replacing fuel filter the car had no power at all and was shacking under full throttle)

the spark plugs i did not replaced yet. ( i bought genuine volvo ones and will replace soon)

symptoms beside this starting problem:

- smell of fresh gas after the engine is warming up (only in town driving or if i rev it on stop) in extra urban i don't smell any.
- on full throttle, the car feels like is losing power ( if i accelerate gradually, feels normal)

these problems could be related to fuel system? maybe the fuel pump has dirt in filters or is just tired and not working correctly? or could be the FPR ? i don't smell any fresh gas in the engine bay.


regarding FPR, has anyone replaced genuine PN with this alternative Marelli part number - 219244340501 or BOSCH Fuel Pressure Regulator 0280160557? these are alot cheaper...would be great if they fit.

thank you in advantage for any advice.