Hi, while it may be a bit challenging to know/learn the exact position of a feature programmed into your MPI engine model PCM called Clear Flood Mode as the throttle position percentage valve’s change from engine models, manufacturers, etc., they all tend to have clear flood mode… Some operate this feature at 25%, some 50%, some 75%, some 100% throttle…
What this feature does is turns off the fuel injector pulse width while cranking the engine over to start using the key. The design is ‘should you happen to know for sure the fuel system is actually putting out to much fuel and starting to flood the engine cylinders of fuel making it hard to start like sometimes seemed to happen back in the carburetor days of having to open the throttle to wide open for a bit of time to help dry things out for an easier start, with EFI’s putting the throttle at the right position helps to not add fuel if known flooded
Part 2 of opening the throttle if not actually flooded is should the Idle Air Control valve if available on your exact engine type/model/design has gone bad not allowing air in at 0 % throttle then by you opening the throttle you’re bypassing the IAC and giving the engine air to hopefully start up… Plus in turn drying out a flooded engine if that’s actually happening.
You might want to pull out your spark plugs to see if they appear fouled any.
What engine temperatures are you getting up to?
Could be a fuel pressure issue, running too cold or the MPI temp sensor (different then the temperature gauge sensor) thinks it’s too cold adding to much fuel or maybe a few other possible sensors that help operate the fuel Pulse width to the injectors are out of range adding fuel.
Performing an engine scan to the MPI system may help narrow things down of what’s right and what’s wrong and/or performing a fuel pressure check to ensure the fuel psi is within specifications.
Hope it’s an easy fix for you, good luck.
