Just within the last week my car is taking longer to start when the engine is cold; or after sitting overnight/6+ hours. If the engine is warm, it fires up normally.

The starter cranks normally, just does not fire after 2-3 seconds like it always has. Battery is good and is less than 2 years old. Once started, engine idles normally, car drives normally, and there is no loss in power or studdering throughout all RPMs from what I can tell. It started happening last week after I drove on empty longer than I should have, I filled up 19.4 gallons. I know that is really bad for our pumps. Now it every cold start it takes 5+ seconds and alittle hesitation to fire up.

I've done some reading and its possible I need a new fuel pump? I've read our fuel pumps overtime, leak and dont maintain pressure for cold starts? Driving on empty overheats them since they are cooled by gasoline in the tank. I'm aware of the infamous camshaft/crankshaft sensors going bad, but I have no SES light. I have a 2005 5at sedan, 101K miles, spark plugs changed at 90K, all routine maintenance performed. I have used Shell 93 octane religously for the past 4 years, this would be the first fuel related issue I've ever had.

 

Are you experiencing a 30+ degree swing in ambient temperatures where you live? If so, I bet it's the battery. It may still be putting out the right voltage, but what matters if the amperage, more specifically ... the CCA (cold cranking amperage), which is diminished with with big temperature swings.

 

I do live in Chicago, it is quite common to be 65 one day and 27 the next day . But I am pretty confident its not the battery. Its not cranking slowly like a weak battery would cause. Its cranking fully without firing right away on cold engine startups. Tomorrow morning I am going to let the fuel pump prime (wait a couple seconds in ACC mode) before I try to start the engine. That might tell me if its a loss in built up fuel pressure while the car sits overnight.

 

Instead of ACC put it in the ON position and wait 2-3 seconds. (you can hear the fuel pump cycle if you're in a quiet enough area)

 

Sorry.. meant to say ON. I tried leaving it in ON position for 5 seconds a few times now, but the engine still hesitates to start when cold.

So my car threw a SES light while crusing on the highway. I had it scanned and its code P0455 which can be 1 of 4 things:

1. faulty fuel cap
2. purge system leak
3. faulty canister vent control valve
4. faulty purge control valve

Could any of those things cause the starting issues I am having?

 

Can P0455 cause hard cold starting? I have replaced the fuel cap, and vent control valve in the rear of the car and reset the SES light. It came on a day later, 10 minutes after a really rough cold start, engine made a really bad clunk right before firing. But the engine starts flawlessly when warm! I'm going to have to take it in to Nissan tomorrow, but anyone have any idea what could be wrong?

 

Figured I would update this thread. Nissan hooked it up their smoke machine and found the leak at the vent control valve. Apparently I didnt insert the new valve properly and I pinched the O-ring. On a better note my car has been starting normally now.

 

The past couple mornings I have had the same problem on start up but nothing else so far. I live in Northwest Indiana so weather is the same. Battery is less than a year old so its not that. I may have the same problem. Was it hard to fix?

 

It has been warmer the past few days, which makes me think is helping. Maybe they switched to summer blend gas, and the cold weather we've had is not helping? I still dont fully understand how the EVAP system could effect startup. My car started up normally yesterday and today, both times it was in the upper 50s.. It actually started up fine before I took it to the dealer, go figure.