F150 Hard to start when hot

[seahunt18]

I have a 2006 F150 4 strokes. The engine has been running great until last summer. I have what I believe is a vapor lock problem. After running above 3000 RPM for more than 10 minutes, the hot engine would not start on the first crank after sitting for about 15 minutes. I would have to crank it for like 10 seconds or so, it would sputter and start very rough but smooth out very quickly. If I wait an hour or so later, it will start as normal on the first crank. Here's my only "solution" to the problem so far. I found that if I remove the engine cowling when the engine is hot, it would start up fine after sitting for 15 minutes. I checked the cowling and find nothing that would obstruct the air circulation. Any suggestions?

[99yam40]

I believe that motor has a fuel cooler, might check to see if the water flow thru it is good.
it maybe vaporizing the fuel in the VST causing an over rich condition at hot start.
also make sure the IAC is opening to 100 percent what the motor is shut down

[seahunt18]

I believe that motor has a fuel cooler, might check to see if the water flow thru it is good.
it maybe vaporizing the fuel in the VST causing an over rich condition at hot start.
also make sure the IAC is opening to 100 percent what the motor is shut down

Water is coming out of the pee-hole so I didn't think that the fuel cooler is clogged. I'm sorry but what is the IAC ? Thanks

[99yam40]

Idle air control valve

[99yam40]

Water is coming out of the pee-hole so I didn't think that the fuel cooler is clogged. I'm sorry but what is the IAC ? Thanks

does the tell tail on that motor indicate water flow thru the fuel cooler?

[pstephens46]

Ok. I have a 2005 model year. Same issue for 8 years. If you find a solution, let me know. They put a carbon canister in later models. Rodbolt explained to us....not vapor lock..it’s a rich condition in the air box. Motor gets hot and fumes are dumped into the intake. Sitting for awhile allowing air to circulate allows it to resolve itself.

Whatever. Not going to add carbon EPA nonsense for 1000s with no guarantee. My F150 has been bulletproof. Short intervals of sitting after hard runs are worse.

Best way to start a grumpy hot motor? Use the neutral button at base of throttle. Advance to 40% . Start cranking. As you are cranking, slowly close the throttle. Motor starts every single time. Inhale the gas fumes and enjoy. You haven’t hurt a thing!

[seahunt18]

does the tell tail on that motor indicate water flow thru the fuel cooler?

Yes the hose that comes out of the bottom of the fuel cooler is connecting to the pee-hole. Should I try replacing the IAC? I think I can get a used one on Ebay.

[seahunt18]

Ok. I have a 2005 model year. Same issue for 8 years. If you find a solution, let me know. They put a carbon canister in later models. Rodbolt explained to us....not vapor lock..it’s a rich condition in the air box. Motor gets hot and fumes are dumped into the intake. Sitting for awhile allowing air to circulate allows it to resolve itself.

Whatever. Not going to add carbon EPA nonsense for 1000s with no guarantee. My F150 has been bulletproof. Short intervals of sitting after hard runs are worse.

Best way to start a grumpy hot motor? Use the neutral button at base of throttle. Advance to 40% . Start cranking. As you are cranking, slowly close the throttle. Motor starts every single time. Inhale the gas fumes and enjoy. You haven’t hurt a thing!

Mine is a 2006 and it has the carbon canister box. How long do you normaly have to crank when using the neutral button? Without messing with the neutral button, mine would start if I crank it for about 10 seconds straight..

[pstephens46]

Mine is a 2006 and it has the carbon canister box. How long do you normaly have to crank when using the neutral button? Without messing with the neutral button, mine would start if I crank it for about 10 seconds straight..

10 seconds at the most. Fishing is where it really comes into play. Run hard between spots. Fish for 15 minutes at the most. No bites? Haul ass to the next spot. That is where the issue really comes into play. My motor has overheated only once. My fault, mud related. I am amazed at how reliable it has been. 15 years and still the same.

[pstephens46]

Don’t throw parts at it........

[99yam40]

Yes the hose that comes out of the bottom of the fuel cooler is connecting to the pee-hole. Should I try replacing the IAC? I think I can get a used one on Ebay.

I said check to see if it is working properly, not replace it.
Should hear it rattle when you turn the key off resetting from next start up.

[seahunt18]

I said check to see if it is working properly, not replace it.
Should hear it rattle when you turn the key off resetting from next start up.

Yes I do hear that rattling sound when shutting the enigne down.

[seahunt18]

10 seconds at the most. Fishing is where it really comes into play. Run hard between spots. Fish for 15 minutes at the most. No bites? Haul ass to the next spot. That is where the issue really comes into play. My motor has overheated only once. My fault, mud related. I am amazed at how reliable it has been. 15 years and still the same.

Have you service the VST?

[username]

Might be a leaking injector? Injector service is relatively inexpensive.

[pstephens46]

Have you service the VST?

Yes I did. It was clean after 8 years of use. I sprayed the filter and reused it.