Can't start when hot, back to normal when cools down

[nirvanaws]

This is an old problem since i bought the car (2003 explorer sports XLT ) since 2010.

When it is hot (above 90 degree), it cranks OK but won't start (dash board display seems normal, no code left), after let it cool down for 2 hours, it starts normally without any problem --- as if nothing happened. Someone suggested me to listen to the sound of the fuel pump, but i can't get it even the car can start normally.

Here are what i experienced:
1. I seldom have this problem (even on hot days) when the gas tank is full ( or nearly full), and it happens more offen when less than half full.
2. Once i got the car towed when it won't start on hot day, after towed 1 miles, it can start normally (won't start when we are trying to tow it), so the shaking on the 1 mile may help it recover.

Tow truck guys told me it might be a fuel pump problem, and i should test the fuel pressure first.

i bought a fuel pressure tester and trying to test the fuel pressure next time when it can't start on hot day, just check the engine under the hood, but can't locate the test port. Here are the photos, can someone point a direction?

driver side of the engine.
https://onedrive.live.com/embed?cid...AD1F61C93F1304C!10777&authkey=AG4cGj85XZKlOfo

passenger side of the engine.
https://onedrive.live.com/embed?cid...AD1F61C93F1304C!10778&authkey=AA_7yhLZzRltIsg

thanks.

 

[01DeepBlue]

I can tell you that the most probable cause of your problem is the ignition module. Your symptoms are a text book case for it. When an ignition module is no good and it gets hot it can cease to function until it cools off. Sometimes it will just fail completely and never work again but when it is intermittent like in your case it is affected by heat.
The engine or even outside weather being hot or cold wouldn't have any effect on the fuel pump. The fuel tank under the car with many gallons of gas in it will remain relatively stable in temperature and electric motors aren't usually affected by small fluctuations in temperature. It would be completely unpredictable whether or not the fuel pump would pump or not if it was on it's way out. I'd change the ignition module or at least see if you have any spark when this condition occurs.

 

[Phantom]

I had a GM that did the exact same thing. Turned out to be the crankshaft position sensor. Just a thought.

 

[Travisfab]

Had that issue with my bronco before. I would splash the starter with water, and it would start. Starter was bad obviously .

 

[01DeepBlue]

Had that issue with my bronco before. I would splash the starter with water, and it would start. Starter was bad obviously .

I said "small fluctuations in temperature" don't usually effect electric motors. I had a 1979 F-150 that would heat up the starter from the exhaust and it would keep the starter from cranking over too. Obviously, we're talking about wide temperature differences in such a situation. A hot engine can raise the temperature of a starter by quite a bit.
A fuel pump in a fuel tank under the shade of a vehicle with many gallons of gasoline in it will not experience 100 + degree temperature differences from one day to another(or anything even close to that). I'm just saying you can probably rule out temperature affecting the fuel pump and if it was it definitely needs to be replaced.
Also, his engine cranks over. It just doesn't start so it's likely fuel or ignition causing the issue. Either one is easy to test when this no start condition occurs. A fuel gauge on the fuel rail and pulling off a plug wire while holding the end of it up to metal to check for spark.
The crankshaft position sensor is a possibility as well just as Phantom suggested.