2003 trouble starting after car is warmed up

[jsword47]

Car always started immediately upon turning the key. Still does, but only when cold. When warm, it cranks for quite a while.
Any ideas?
I think it's a sensor

 

[tmdtmd]

Think low compression, posibly manageable with a heaverier grade of motor oil

 

[jsword47]

Thank you for your suggestion but would low compression affect starting when the engine is cold?
I should have added car runs very well.
Merry Christmas, John

 

[tmdtmd]

Yes the air in the cylinders are cold and more dense. Runs well once the car is running, the oil from the oil pan coats the cyliner and increases the ring seal until you shut it off. Then the hot oil drains back into the pan. You might even consider STP or something along that line to make the oil a little more sticky.

 

[doug7740]

Thank you for your suggestion but would low compression affect starting when the engine is cold?
I should have added car runs very well.
Merry Christmas, John

Before you get to far down the rabbit hole, use a scan tool to see if there are any faults that might tell you why there is a hard starting issue with your car when the engine is warm.

doug7740
1955 Thunderbird Blue

 

[jsword47]

Starts immediately when engine is cold. But when engine is warm, cranks for about 10 seconds before starting. Why?

 

[Daily Driver]

Same problems years ago on 4.6 Cougar, fuel regulator. I would also get a smell of fuel at times