I have a 2005 Kia Sedona Van it is miss firing at #2 cylinder. Had the ignition. coil for that unit replaced, did a tune up twice,, and checked the engine for loss of pressure it was good. What is left to do?

What does the computer codes say is wrong? You should always check the codes before you start buying parts you might not need.

If you've done a coil and plugs then it could be a bad head gasket, a bad intake gasket, a bad injector.

Check for codes. Problem may be a vacuum leak. Attach a scan tool and check the short-term and long-term fuel trims. If both are decidedly negative, the problem may be with the ignition system (e.g. plug wire or PCM spark driver); if both are significantly positive (greater than 5%), look for a leak. Check the fuel injector and its wiring, plug gap, and coat the top of the electrode and porcelain portion of the plug with dielectric grease. If the problem persists, the oxygen sensor may be a factor. Only use the exact same plugs that originally came in the vehicle.