2004 GX350L Hyundai and dies sometimes and lags but in very good condition.. I was thinking of the fuel filter and found out it was in the tank but I'm not so sure now??
Try cleaning throttle body and add some fuel injector cleaner to gas tank also check air filter.
this happen to me check fuel pump relay may have a bad connection the relay gets hot well driving and makes bad connection the heat from relay makes socket weak easy fix pull it out bend pins a little and put back in
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