Hyundai Repair: Accent, fuel pressure gauge, fuel pressure regulator

Question
My 1995 Hyundai Accent is causing me fits.  This is what is happening.  Sometimes my car won't start.  It cranks find but just won't go.  However after cranking for sometimes 15-20 minutes it will go.  Also after it does go it will buck when starting at stop lights but once it finally accelarates it is find.  Also many times it feels like it losing power when driving and I have to push the accelarator harder to maintain speed.  Finally a lot of times there is a lot a smoke coming out of the exhaust.  It also burns some oil but not a excessive amount.  I have replace the air filter and sparkplugs and ignition wires.  I have been told a lot of different things it could be but I would like to narrow it down.  Thanks

Answer
Hi, Ray.  Unfortunately, I'm not going to be able to do much narrowing for you since I don't have the car to diagnose.  But I can give you some pointers as to how to approach the problem.

First off, if your check engine lamp is coming on, start there.  Find out what the trouble codes are.  That'll give you a big hint as to where you should be looking.

Starting with the long crank, we should be looking at things like the fuel pressure regulator, the fuel pump, and the crankshaft sensor.  If you've got a fuel pressure gauge, install it on the vehicle the next time you have an opportunity after coming home.  Tape it to the windshield so you can observe while driving.  

Install the gauge and start the car.  It should register about 35-40 psi.  If it's significantly lower than that, you probably need a new fuel pump.  Then turn the car off and let it sit for a few hours.  It should retain about 20 psi.  If it doesn't, you need a new fuel pressure regulator.  If you can, tape the gauge to the windshield and drive the car and observe the readings.  They should be the 35-40 psi mentioned above.  If they're low when the vehicle starts performing poorly, you'll need a new fuel pump.

There are a number of possible causes for the lack of power.  If you are unable to tell whether it feels like the car is misfiring, has low fuel pressure, or has a clogged converter by driving the car, then this diagnosis is probably most quickly and accurately done by a professional (if it hasn't been cured due to the previous paragraph).

As for the smoke, I'll have difficulty giving you information about the cause unless I know when it occurs.  Does it occur:
On cold starts?
When idling for a long period?
On acceleration after being stopped?
On acceleration while already driving?
After driving for a particular period of time?
In conjunction with any of your other problems?