Hyundai Repair: 2001 Tiburon intermitten starting problem, coolant temperature sensor, fuel pressure regulator

Question
Hi,

have a 2001 Tiburon 2.0L, has 170K kilometers on it originally from Canada now in Phoenix, AZ, recently, over the last week or so, have had problems starting the car, but only when it has been sitting for a couple of hours, in the morning when leaving for work, and in the afternoon when going home. try to start it and it turns over but doesn't seem to want to start, then after a couple of tries it will go. just changed the battery about a month ago.

Answer
Presuming the engine cranks at normal speed, I'd suspect a problem with the crank sensor, coolant temperature sensor, air flow sensor, or fuel pressure regulator.  In order to determine where to look for the problem, it'll be important to run some tests when the problem is occurring.  If you have no spark, it suggests that the crank sensor may have failed.  If it takes a long time to build up fuel pressure, it suggests that your fuel pressure regulator is bleeding off fuel pressure while the engine isn't running.  If you have both spark and fuel, then the suspects move toward the coolant temperature sensor and air flow sensor, which, if giving erroneous readings, can cause the engine control module to mismanage the fuel mixture.