Then if its not possible to get vapor lock what else might cause it it seems that when I drive it on the highway then get off
it starts to idle rough then stalls and it won't start unless I spray quick start and it,only seems tobe when it is hot out.
uick start or i let it sit over nite could it be the gas cap?
First.. Did you ever check your gas cap to ensure it was a venting gas cap? and why start a new thread? Do you have any check engine codes? If fuel vapor recirculation system is not working correctly, it would flag a check engine light. Could also be a bad EGR... Your EGR opens when on the highway, if it is sticking open, when you slow down it would start to idle rough and eventually stall. (This is my primary guess). Spraying quick start only overloads the sensors and puts the system in a temporary closed loop set up bypassing all sensor reads. It should have a higher idle at this time (which is why it stays running).
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