Ive got a 2004 gets diesel it starts difficalt hyundai told me the one injector has a diesel leack.that they have fix now there is smoke comming out of the oildipstick while ideling

no year told ,2006 to NOW.
no country told and not sold in USA> Australia I guess.
no engine told,, nobody can guees 6 engines and is an engine question, seems you messed up , but not told why all this started so answers , impossible.

2.5 L MZR-CD I4 (turbo-diesel)
3.0 L MZR-CD I4 (turbo-diesel)

• 1.9 L RZ4E-TC GEN2 I4-T (diesel)
• 3.0 L 4JJ3-TCX I4 (diesel)

• 2.2 L MZ-CD diesel I4[5]
• 3.2 L MZ-CD diesel I5

Is your vehicle a petrol or a diesel? Black smoke is a sign your engine is burning a fuel mixture that is too rich, (Too much fuel, not enough air). Start by replacing the AIR filter. After that you need to get the fuel injectors checked. If yours is a diesel have the EGR valve checked as a sticky valve isn't diverting unburnt fuel back through the fuel system.

air in fuel system
glow plugs not working
engine cranking speed to slow
(diesel engines have to crank at a high speed to get the compression high enough to ignite the atomized fuel)
injectors squirting --not atomizing
injector control module failing

Thanks for telling us.

Sounds like the valve guides are leaking oil into the cylinders, or there is a coolant leak somewhere. Usually white smoke is coolant but could be oil.
Are you adding either fluid often ?

When you change it, fill it with fuel before you put it on. This will help from have to open an injector. It might smoke for a minute, but this normal. If it doesn't want to start then loosen up a line on any injector, crank the engine untill fuel cmes out. tighten it up and it will start.

If at all possible, get a second opinion. Preferably someone who specializes in diesel service.

CHECK INJECTOR LEAKAGE
COMMON FAULT WITH BOSCH INJECTORS

Not sure what you mean by "heavy on diesel".   Most diesels, except for late models say 2005 or newer, will have a tiny amount of smoke when cold.  It's hard for a cold motor to combust diesel without a little smoke.  
My money would be on one or both of the other two injectors, dirty, dripping or bad spray pattern.  If you near anything lke a small city, you may be able to find a shop that has the abilty to clean and check them. I use a big marine diesel shop, RPM, in Ft Lauderdale, they can generally get injectors back to new for cheap (maybe $30 each) and have a big expensive high tech machine to test them (they can afford to, they use them for engines on million dollar yachts, among others).  The hyundai injectors might be cheap, the Bosch ones are not.
Injector cleaner in a can that the parts store is happy to sell you, has not worked for anyone I know.   
If you ever lay the car up (e.g. go away on holiday for a month so) put additive in the diesel to keep bacteria from growing in it.  If you can't get it in the auto store, try a marine store.

post your question on toyotadiesel.com forums lots of members have the same rig as yours and would be able to give better advise/remedy.