Thread from 2015
I'm beginning to suspect my fuel pressure regulator is not quite 100%. Two or three times it has not started right away, but started on the second try after 3-4 seconds of cranking. Car is a 2006 Subaru Outback XT, turbo with automatic transmission with 103K miles. If I pull the lines from the fuel pressure regulator I can, sometimes, get the faintest smell of gasoline. It's $370 for a new one on Rock Auto so I need more than a hunch to go ahead and replace it. This might also be the fix for my recurring check engine light. That CEL hasn't been a priority but I definitely want to fix this before an occasional hard-start becomes a no-start. Thanks for your wisdom! David
I could be totally wrong here...
I would think that even with low pressure an engine would start and idle (the fuel requirement is like literally nothing).
I would expect to see issues under load before you would see them at idle or start.
What is the check engine light on for?
Check your fuel pressure. If the regulator is failing, it's probably low on pressure which will cause a hard start issue. It could also be bleeding off pressure while sitting which can also cause a hard start. It should hold pressure for a while.
Here's a pretty good link for common tests. At $370 for the regulator, I'd spend a while making sure that was the problem.
http://www.agcoauto.com/content/news/p2_articleid/323
does it start right up if you turn the key to "run" and let it prime a few times before actually starting it?
My brother had a similar issue but with a jeep, it's the antidrain back valve at the fuel pump that keeps the system primed. As others stated, check fuel pressure first cause that's an expensive fuel pressure regulator
Fuel pressure regulators have several failure modes- your symptoms suggest its not holding rest pressure, so the pump has to run a while to build enough to start the engine. (Novaderriks test is a good diagnosis for that.) Second failure could be a leak of fuel to the vacuum side, but on a Subaru that shows up as a long crank followed by misfires on the side of the engine that the vacuum hose runs to. When that gets really bad, it will flood the engine in a rather exciting manner. Third failure involves it sticking shut, which spikes the pressure and overfuels the engine. Fourth would be stuck open, making it run lean or not start at all.
Putting a test gauge on a Subaru is easy, parts store rents them.
