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The car starts OK when cold but cranking long when warmed up.
Okay assuming the O2 sensor is telling the truth and I assume it is a cranking no-start.
Often cranking no start issues can be down to crank or cam sensor issues, or on engine with a single coil the coil.
However the knock/pinking (pinging) makes me concerned about valve timing or carbon build up or even something as simple low coolant level.
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" We're trying to plug a hole in the universe, what are you doing ?. "
(Walter Bishop Fringe TV show)
So is it just a crank - no start when hot or does the engine stall as well when hot?
If the owner shuts off the engine is it difficult to restart immediately or does it take a short while with the engine off to make the problem happen?
You may look for a valid rpm signal on the scanner or tachometer during the no sart situation...
An expert is someone who knows each time more on each time less, until he finally knows absolutely everything about absolutely nothing.
The way I read the post is long crank when hot first thing that comes to mind is vapor in fuel line from hot soak you can verify by adding starting fluid when it would normally be a long crank (after hot ) however if it's a hard start immediately after shutting engine off then that would really put a damper on this theory ...
