2003 nissan maximal 3.5 v6 engine just shuts off sometimes will crank back sometimes want crank just turn over till u push gas to floor and hold it

my answers are do a tuneup and use tools and do test to find cause. not me guessing. okk?
no MILES on car told. 100k 150k ,2ook
are you ignoring the cam belt v6 , not replaced at 60 to 100k miles and if snaps engine is now a wreck.?????
means this old belt 2000 old. 23 years old is no GOOD.

turn it over means? cranking but does it crank fast or slow. ???? if fast that is cranks fast no start engine.
no engine told at all, no clues.
3.3L USA engines is common here.v6 or 2.4L I4????
6 engines used word wide but not USA.
and 2 diesel engines, you never said DIESEL.
2.4L is chain drive cam , 3.3L is belt. (key point )

I will guess the V6 usa spec engine,
if engine is good , compression tests pass. (a tool)
and fails to start, there are these reasons
all fuses checked good,transmission can shift all gears.
you said GAS so I guess gasoline, not LPG or the like.
only good clue was GAS.( and engine runs bad)
2nd google clue is smoke+ flooding, sure.!! wasted fuel sure.
first off no engine runs good if spark is bad (otto cycle gas)
nor if engine is bad. (compression below 150psi) a tool.
my wild guess, no tune up done nor new cam belt ever put in V6. (right)? service history matters.
checks ,actions and tests, using tools.
v6 gas.
1: spark parts bad. ( called a full tuneup)and cam belt
2 new distributor cap,. rotor , 6 new spark wires and 6 new spark lugs, (a tune up and new air filter.)
now spark is good.
3(so when it does not start scan the oBD2 port with a scan tool. see P03xx errors ?????????
4:fuel pressure at spec, idling and throttle max for 1second (called gunning engine(right foot) using a tool.
fuel rail pressure tests using a TOOL.
5: fuel pressure too high is FPR bad. or too low.
FPR is on the fuel RAIL. and loves to fail this old. !!!!!
fuel pressure reg. (tested with a tool, during injector bala
Learn:
the dealer can NOT find it because it ran perfect that day so they feel compelled to guess. (and make money) buy your own scan tool and not go broke at dealers.
learn to do a tune up first (called service points)


(so when it does not start scan the oBD2 port with a scan tool. and behold P3xx errors or others.
called by kids today me scan tool throws a code
sure a DTC. write them all down and get help.

First start by having the codes read and we can go from there.

Most likely causes are bad engine coolant temp sensor OR leaking fuel injectors. Bad engine coolant temp sensor will give computer false reading and computer provides wrong air fuel mixture. Leaking fuel injectors will load the engine with raw gas--just like flooding it. Try pushing the gas pedal to the floor and holding it there when cranking when hot. That forces the computer into "clear flood" mode and it shuts off the injectors. If it starts up with pedal down, that would be a sign of leaking injectors.

depending on if your buick has the DIC option, it could be 1 of 2 ways.

1. Turn key to accessory (key on , engine off)
2. depress mode button on the DIC display til you see "oil life left/hold to reset
3. Hold set button down till it says 100%
4. listen for 3 chimes
5. start car and see if its reset, if not, it wasn't reset, repeat steps 1-4.

If you don't have the DIC option, then:

1. Turn key to the "key on, engine off" position
2. Depress gas pedal to floor slowly 3 times, make sure you get the 3 presses to the floor within 5 seconds.
3. turn key off.
4. see if the light goes off.. if not, repeat the steps 1-3

a oil gauge reading maybe delayed until car starts and builds good oil press.Did you check for spark
was car running good before this happened? Do you have a rpm reading when cranking car?

i think you might be right it sounds like your engine is getting over fed fuel you are probably not getting very good fuel mileage either the 3.8 and 5.0 would defintely require the same volume of fuel it is probably playing havoc on the pressure regulators i would get another fuel pump and start there

3 to 5 seconds is not really excessive. You might, however, want to try this...depress the gas petal to the floor then turn the ignition while slowly raising you foot off the accelerator. If this helps start the car the check engine light is probably indicating an oxegen sensor problem.

You pinched the fuel line????
If you crank for too long to start the car, the engine will "flood", this is why the plug was wet. It had too much gas and wouldn't start.
Pull out ALL plugs and dry them off.
Install them.
HOLD your gas pedal to the floor and crank.
This will stop gas from entering the engine.
you need to get that extra gas out beofre it will start.
If you have so much gas in there you can do damage to your engine!!
Now after a few crnaking attempts with your foot to the floor, take your foot of the gas pedal and try to start it again.
But remember if it doesn't start in 3 tries, you need to do the pedal to the floor once or twice to remove the excess gas.
When you crank the car to start it sprays gas into the engine, even if it won't start. So it very easy to "flood" the engine, and then you'll have a hard time to get it going!

Local mechanic determined engine was flooded and started it by holding throttle to the floor and cranking 5-7 seconds - then the engine sputtered to life. It has run perfectly before and since and I'm at a bit of loss to understand why this occurred this one time - so far. It's been driven now 5 days with no problems.

1. hold gas pedal to floor while trying to start. do not pump pedal.
2. holding pedal to floor is how you start a flooded f.i. engine