Mazda Repair: starting problem, fuel pressure regulator, regulator failure

Question
Occasionally when starting our 2001 miata, it turns over fine, then slowly starts
to fire, then runs fine without any hesitation at any speed. There isn't any smoke
just slow to fire. Can it be the fuel pump not turning on?

Answer
The issue is fuel pressure or delivery related under most situations.  1999-2005 models have the fuel pressure regulator mounted to the pump assembly in the tank.  Some have experienced regulator failure issues.  A replacement part Mazda BP4W-13-280 is available and may resolve your issue.  In some cases the fuel pump has been to blame.  Pressure stability testing is the only way to determine a flow or pressure issue.