Engine is having problem starting on warm ignition

[gekko668]

For several weeks now my car can cold start just fine but if you drive until the engine get hot, shut it off for 15-30 minutes then try to start the car again, it doesn't start and require 3-4 attempt before the engine will spurring to life. The car is out of MFG and I've already replaced the battery. I'm leaning toward one of the spark plug could be going bad but I want to hear your opinion.

Also 2 years ago I rush to my work place and forgot to turn off the engine and let it run or at least 2 hours and that is when it start to happen. The problem went away after a week of use but now it coming back.

Thanks for replying

[Francesco]

Have you had the fuel pressure regulator replaced?

Frank 2009 Versa S sedan MT-6 with 16900 miles

[gekko668]

I dont think the fuel pressure regulator is going bad at all because once the engine starts, it works great. Another reason why dont think the FPR is bad because when the engine is running it doesn't sputter or stumble at all.

[Andrews Chalmers]

Definitely not the classical fuel pump issue, which usually occurs on the first crank on cold start before the fuel lines are pressurized properly (but would not occur on restarting a warm engine).

By the sounds of it, it seems like your engine cylinder is flooded with too rich of a fuel mixture after the shutoff. Just off the top of my head, could be something wrong with your throttle body, or fuel pressure regulator.

[gekko668]

can the fuel pressure regulator go bad that fast or often? or even the spark plug? my versa is only +32,000 mile on it and its a 07.

[Promise Land]

Definitely not the classical fuel pump issue, which usually occurs on the first crank on cold start before the fuel lines are pressurized properly (but would not occur on restarting a warm engine).

Mine would take a few seconds to crank on a hot or cold engine.

Mine started showing signs at about 19,000 miles. I had it replaced ~ 2 weeks after the first signs of trouble.

[Francesco]

I dont think the fuel pressure regulator is going bad at all because once the engine starts, it works great. Another reason why dont think the FPR is bad because when the engine is running it doesn't sputter or stumble at all.

The object of the fuel pressure regulator is twofold; 1) maintain a steady pressure while the engine is running and 2) maintain good pressure in the fuel rails after the engine is shut off to make for a quick start. The problem seems to be with item 2 when it bleeds down with the engine shut down and it take a while for the electric fuel pump to re-pressurize the system. Mine is acting up in warm weather and does not seem to be a problem in the morning. I get in the car and turn the ignition on and then buckle my seat belt and then try to start; the extra time to buckle the belt gives the fuel pump a chance to bring the pressure up. I plan to wait and get it fixed just before the warranty is due to expire. I am not yet convinced they know the root cause of the problem because it has been going on for many years and it appears they keep making revisions. Another source of low pressure in the fuel rails with the engine off could be a leaking fuel injector.

Frank
2009 Versa S sedan MT-6 16900 miles with average MPG of 33.8

[gekko668]

If what you said is true how much does it costs to have the fuel pressure regulator replace?