2006 LR3 V6 gasoline engine
153K miles

I have been plagued with an intermittent no-start issue for a while.
I thought this was an issue with the evap pump but today, the gas tank was full and it did not start.
this can happen minutes or days after the truck sitting with the engine off. Most of the time, this is hours after running.
once started, it will restart without hesitation.

Symptoms:
- randomly will not start
- engine cranks

Additional data:
- did not start yesterday morning either
- today was cold (35 Farenheit) but temperature does not seem a factor (I.e. not a battery issue?)
- humidity level does not seem to make a difference (today is very dry)
- will always start with starter fluid injected on air intake side
- 153K miles
- air filter clean
- no code thrown
- noise heard when turning key in position 2 from the tank/fuel pump area (no idea if noise heard is appropriate)
- IID tool reports:
- fuel rail temp stuck at -40 Celsius


Happy to report on live values from IID Gap tool if that helps.

 

"fuel rail temp stuck at -40 Celsius" My 4.0L reads the same, so I doubt that is an issue.
Have you tried to cycle the key a few times to the second position, wait a few seconds and then back to off? If it fires reliably on starting fluid, it sounds like it has a fuel delivery problem. The key on-wait-off-repeat procedure may help to build fuel pressure if your pump is weak. Listen for changes in the pump priming sound as you cycle the key. If your pump is weak, you may hear it trying to build pressure. Otherwise, if your pump is operating properly, you probably wouldn't notice the pump building pressure before the engine starts.
Does it stumble or run rough after it starts?

 

Crank position sensor? I really don't know, but recall reading about a similar intermittent starting problem here, and that was the fix.

 

runs great after it starts. No stumbling or rough running.
i can hear the pump run. I have not yet (it’s cold now! ) figures out where the shradder valve is to check fuel pressure. I did not try the “position II a few times” yet. Will try this next time it does not start.

 

that’s definitely a good thought. Now, I would assume that this would make the engine run rough? Maybe throw codes (misfire, etc)?
Also, never say never, but from what I read on the topic the sensor tends to die/misbehave with higher temperature and the issue disappears when engine is cold(er). I’ll still look for known issues like this with the Ford engine!

 

The shrader valve is under the plastic engine cover. You'll see the pipe and cap on it between the intake runners towards the front of the engine. A weak fuel pump will take longer to build pressure as the temperature drops.