My '02 V70 XC has an intermittent issue: at every third or fourth start up it won't idle and wants to die immediately.
after revving it for about a minute it smooths out, then I can drive like normal.
I bought a scan tool and here is what it tells me:
P0442- evaporative emissions system leak (small leak)
PO300 multi cylinder missfire
P0301
P0302
P0303
P0304
P0304
P0305 individual cylinder misfire
Can anyone tell me what they think may be wrong with this car? I'd like to find out if I can fix
this myself, or find a reputable import shop that can help. Thanks in advance.

 

P0442, would start with your gas cap. Check the gasket for damage.hardness. Replace if damage found.

All the rest refer to misfires of all cylinders. P0301 cyl 1, 302= cyl 2 and so forth. Have you recently had a spark plug change? Could be as simple as wrong plugs.

 

Since this issue is not causing my car's symptoms, should I go ahead and replace
the fuel pressure sensor?

 

The leak can be very small and located anywhere in the EVAP system including the gas cap, hoses, purge valve and vent valve. A more advanced scanner will tell you how much pressure is being lost. Like you, I might replace the fuel pressure sensor because it is cheap and accessible, but if not the problem you are throwing money at it trying to guess. There is a different code specifically for the fuel pressure sensor, so that might not be it at all, but could be. A qualified mechanic would use an analyzer that reads data from the different modules to locate it, or possibly do a smoke test.