No Start When Warm
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Junior Member
Joined: Feb 2026
Posts: 4
No Start When Warm
Good Day!
I have checked this forum, the internet, manuals and multiple friends and I cant seem to find the answer to my issue. I came to this forum in hopes someone would have an answer.
2011 F250, 6.2L, 4x4, 4D-SB. Truck was/is throwing multiple evap codes. filling up the truck was/is almost impossible. The pump would lick off with just the slightest fuel being pumped. Takes about 10-15 min to put in 5 gallons.
Fuel pump sending unit was not working. Gauge read empty all the time.
i pulled the bed and replaced the fuel pump/send unit assembly. I also replaced the evap vent valve because of the code being thrown.
when I replaced the fuel pump the truck fires right up, first crank. Ran smooth as ever. I got the bed back on. Fired it up again to double check and it ran great. Turned it off again and finished up some things. I took it for test drive to go get pizza for the fam. About a 3 mile trip, around 4 minute's and only 35-40mph. I go inside to get the pizza, about 10 minutes, come back out and truck will not start. Cranks and cranks and cranks. No start.
I get a ride home, do some reading, read some things about heat sink, cooling etc. Go back 2 hours later and it STARTS PERFECTLY. Truck runs smooth and idles amazingly. I drive home with no issue.
once home, I turn it off, count to 3, and try to start it. It fired right up. Turned it back off. Gave it 30 seconds. Starts first crank. Turned it off. Gave it 10-15 min. Will NOT start. Crank and crank and crank. Wont start. Came back 30 min later, still wont start. Gave it 1.5 hours and it fires perfectly.
It has never done this before. Any ideas? Is this an evap issue? Purge valve? Bad fuel pump? Fuel pump driver module? Any help is much appreciated.
I have checked this forum, the internet, manuals and multiple friends and I cant seem to find the answer to my issue. I came to this forum in hopes someone would have an answer.
2011 F250, 6.2L, 4x4, 4D-SB. Truck was/is throwing multiple evap codes. filling up the truck was/is almost impossible. The pump would lick off with just the slightest fuel being pumped. Takes about 10-15 min to put in 5 gallons.
Fuel pump sending unit was not working. Gauge read empty all the time.
i pulled the bed and replaced the fuel pump/send unit assembly. I also replaced the evap vent valve because of the code being thrown.
when I replaced the fuel pump the truck fires right up, first crank. Ran smooth as ever. I got the bed back on. Fired it up again to double check and it ran great. Turned it off again and finished up some things. I took it for test drive to go get pizza for the fam. About a 3 mile trip, around 4 minute's and only 35-40mph. I go inside to get the pizza, about 10 minutes, come back out and truck will not start. Cranks and cranks and cranks. No start.
I get a ride home, do some reading, read some things about heat sink, cooling etc. Go back 2 hours later and it STARTS PERFECTLY. Truck runs smooth and idles amazingly. I drive home with no issue.
once home, I turn it off, count to 3, and try to start it. It fired right up. Turned it back off. Gave it 30 seconds. Starts first crank. Turned it off. Gave it 10-15 min. Will NOT start. Crank and crank and crank. Wont start. Came back 30 min later, still wont start. Gave it 1.5 hours and it fires perfectly.
It has never done this before. Any ideas? Is this an evap issue? Purge valve? Bad fuel pump? Fuel pump driver module? Any help is much appreciated.
Thread Starter
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Junior Member
Joined: Feb 2026
Posts: 4
the 6.2 doesn't have a fuel pressure test port. It’s all done via scanner which I do not have nor am I going to spend $1k on. Fuel rail pressure regardless, still asks the same question. Why fuel pressure when cold and no fuel pressure when hot?
Thread Starter
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Junior Member
Joined: Feb 2026
Posts: 4
Spark plugs can tell you a lot ,,,,,,,,,if you know what you are looking for !
If you remove any spark plug when it won't start,,,,,,,,,,,,,,,and look to see if it is wet or dry
If wet fuel is getting to the combustion chamber. If dry ,,,a fuel supply problem. Includes possible injector, fuel pump OR power to either not present
If too much fuel, that can also prevent it from starting.
If we need to verify spark is available at the plugs.You can remove one of the plug wires, place a screwdriver in the end, place the shaft of the screwdriver about a 1/4 inch from any metal part of the engine and have someone crank the engine over and watch to see if a spark jumps that space. You will either see the spark or not see it .
If you don't see it , there is an ign syst problem.
If you remove any spark plug when it won't start,,,,,,,,,,,,,,,and look to see if it is wet or dry
If wet fuel is getting to the combustion chamber. If dry ,,,a fuel supply problem. Includes possible injector, fuel pump OR power to either not present
If too much fuel, that can also prevent it from starting.
If we need to verify spark is available at the plugs.You can remove one of the plug wires, place a screwdriver in the end, place the shaft of the screwdriver about a 1/4 inch from any metal part of the engine and have someone crank the engine over and watch to see if a spark jumps that space. You will either see the spark or not see it .
If you don't see it , there is an ign syst problem.
Ill dig into this today, Ill have to go get it up to temp and Ill report back. I also read a bad purge valve could cause vapor-lock type symptoms if it’s bed? Any heard this before?
Thread Starter
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Junior Member
Joined: Feb 2026
Posts: 4
If you can read up a little on what a purge valve does and when it does it ,,,will help answer your question.
Purge valve is normally closed. Opened when certain conditions (Monitor is run) are met to empty vapor from charcoal canister where vapors are stored..
Once you have a basic understanding of how the emission system works the mystery will be gone.
Purge valve is normally closed. Opened when certain conditions (Monitor is run) are met to empty vapor from charcoal canister where vapors are stored..
Once you have a basic understanding of how the emission system works the mystery will be gone.
lol I have a complete understanding of the system. Unfortunately your comment really didnt help. Saying “go read” isnt helping the issue and many would take it as an insult but I dont really have the time for frustration.
Furthermore, after testing, the purge valve is pulling vac AT ALL TIMES. This means the valve is bad. And!!! It also means its pulling additional fuel/ gas/vapor or whatever you wanna call it into the system causing lean/rich issues. This was also discussed on another forum i found this morning and is common sign of said starting issues.
additional info for anyone interested. Checked for spark and spark confirmed. Spark plugs are dry when truck is warm and wont start. Pulled the bed and fuel lines. Line to the engine was pressurized completely when I pulled the line. Plugged the line back in, truck fired right up. Checked purge valve, and valve is pulling at all times. Looks like problem solved.
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