2002 Nissan Pathfinder -- Cranks but slow to start

My wife’s Pathfinder (a 2002) has developed a problem with slow starting. The car cranks well (even at -20F, so it’s not a weak battery) but takes a long time to start. It might crank for 5 seconds before sputtering to life. After being driven and shut off, most of the time, it will start up instantly again, just like it used to before the problem started. The problem is intermittent in that it sometimes starts pretty quickly in the morning, although it’s not the instant start that it used to be, it might only crank for 1 second or less. I know that sounds like a normal time for a car to crank before starting, but the Pathfinder used to start, almost literally, instantly after the key was turned. So, even 1 second is an uncharacteristically long time.

What I’ve done:

– Replaced spark plugs
– Swapped the starter relays with identical relays under hood
– Replaced fuel filter

What I haven’t done:

–Replaced fuel pump
–Replaced fuel pressure regulator

Both of these are somewhat big jobs (I think I can handle both of them) and more expensive than what I’ve already done, so I’d like to get some input on where the fault could lie before picking one. Or, am I completely off base thinking it’s fuel system?



Ignition relay?


I followed some troubleshooting guidelines I found on a Nissan tuner forum and checked the vacuum lines from the fuel pressure regulator and fuel damper. There was raw fuel in the vacuum line running from the fuel damper (looks like a slightly oversized FPR with a threaded coupler at the end of a 12" fuel line) which showed that it was faulty. I replaced this part and the car starts normally now!