The crank time is too long(5 to 8 seconds) and there is a fuel smell under the hood. Had a MAF DTC. Replaced the MAF(tried cleaning it first which didn't work) and the SES lite went out on its' own. Still have long crank time and fuel smell after changing MAF. Checked the area around the injector and fuel rail "O" rings for leaks, but can't find any leaks. Not sure if I have two different problems(long crank time and fuel leak) or if these problems are somehow related. I suspect the CKP sensor, but that doesn't tie into the fuel smell.

 

Put a fuel pressure gauge on and check for a leaking injector. If the reading drops 10psi plus within minutes of shutting the engine off you have a leaking injector

 

Crank sensor sends rpm and reference signals to the PCM to begin the ignition fire order as well as other functions.
The Cam Position sensor tell the PCM when to fire the injectors.
You have an ignition issue or excess fuel for some reason.
No or poor ignition and the injectors still work to flood the cylinders.
A fuel pressure regulator can allow gas into the intake independently as well.
One injector leaking should make one cylinder miss until it clears.
Good luck.

 

(I just re-read your original post) Looks like you already checked the O-rings, but I had the same symptoms, and they are cheap, so might be worth checking again. I also found that it helps to check the o-rings when the outside temperature is hot, like 85+ for some reason. Must be that thermal expansion thingy I looked at mine 3 times before I finally figured out that one of them was actually torn and needed to be replaced.

may not necessarily be a leaking injector per se, but rather the injector O-rings. $10 for 8 new rings from autozone. If they leak, it let's the pressure drop in the rail when the truck is sitting.

if it is a leaky o-ring, it's fairly easy to track down, it just helps to have a second person.

with the truck running, open the hood
*have your helper kill the engine, and look / listen for a "sputtering" sound around the top of the engine. Sometimes it helps to have the shroud removed. It also helps to have a flashlight to look at the back injectors.
* if there is one sputtering, you can generally see the "Wetspot" around the injector or coil. pull the fuel rail and change the rings.

What makes it tricky is there is something else under the hood that sputters when you turn the engine off - I think it's the EGR but that sound will be up high, and is a little higher pitched. the injector rings really make a sputtering or bubbling noise when they leak.

hope this helps. Good luck.

Oh, and if you do replace some of the o-rings, make sure you oil them when you re-install the fuel rail, or you'll end up tearing them and starting the job over (yup, been there, done that!)

 

I just did the fuel pressure test. 32 at idle-the range is 30min to 45max.
That part is OK. With vacuum hose to pressure regulator disconnected:42-the range is 40 to 50. That's OK too altho they are both on the lower side of the range. The fuel pump, strainer and fuel filter were all replaced about 1 year ago. The problem shows itself when the key is shut OFF. The pressure starts to bled down immediately. Within 1 minute it's down to 15psi and within 2 minutes it's at 0. That confirms it's leaking fuel. Does this mean it's time for 16 "O" rings since the fuel smell is under the hood area? Did not see any fuel leaking out of the fuel pressure regulator when the vacuum hose was disconnected so I ruled that out as a leak. As quickly as the pressure is bleeding down you would think I could see the leak. I used a bright LED flashlite to look for a wet spot around the injectors, but all I can do is smell it.

 

Spotted a fuel leak on Bank2 @#7. Pulled Bank2 fuel rail and replaced all the "O" rings. Also replaced #7 injector bacause the plastic base was broken. Now no fuel smell and engine starts right up in 1 or 2 seconds instead the former 5 to 8 sec. One caveat. It still bleeds down the fuel pressure to 0 in less than 1 minute after the key is turned to OFF. Should I replace the "O" rings on Bank1? If it's not the "O" rings on Bank1 what else could cause my fuel pressure to bleed down so fast?