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The car has a small block 351w-427R.
It starts up immediately when cold. When warm, sometimes two or three attempts with a couple of seconds of cranking, unless I catch it just right with a few pumps on the gas pedal and just enough pressure on it while I start.
A new fuel pump was installed at the beginning of summer. I don't really remember having this issue before it. The mechanic says its due to the high levels of ethanol in the fuel. It took all summer, but I last week put in 5 gallons of 104 octane and filled the rest with 94 octane to see if this rectified the issue. It didn't.
I've also read it could be the starter not working well when warm.
Any thoughts or suggestions?