01 hyundi santa fe i came up to stop sign pressed brake still in drive,vehicle started struggling like wanted to die.i put in park foot off brake and edle fine...put in drive ,edles rough again

Pull the console apart and locate the release for the shifter inside the console. After you release it and put the vehicle in park, you can remove the key.

Check fuel, spark plugs and wires.

You have what is called Drive by Wire ie. no more mechanical cables.My first question is do you brake with your left foot ? If so,stop.As Majority of newer vehicles are getting more technical and savvy,we tend to forget all the connections and modules ie."Brains" inside our vehicles.This leads to a capacitor discharge where You disconnect both Battery Cables...Negative first, then connect both cable ends with a jumper wire for about 10-15 minutes or longer if you have the time,kinda like resetting your cable modem and wireless unit at home or office...note any auto functions will need to be reset ie..sunroof,auto down/up windows etc. If there's multiple drivers of same vehicle,your vehicle has a learning process on how vehicle is utilized and this can greatly affect performance among different drivers. Mom cruises,the Kid Hot Rods for example.After going through this process of elimination,if you still have the same concern,you may need to set an appointment at your local Hyundai dealer for a Diagnosis as this can be a safety issue and you may just have a bad connection somewhere and it sounds like you're probably still in warranty and should be no cost to you.

did you chek all the fuses

display A6 problam

check coil pack/replace if needed

Ensure your foot is pressing the foot brake before you turn the key, if it is a automatic.
If it is a manual make sure your foot is pressing on the clutch before you turn the key to start it. Most automatic vehicles wont go into gear unless the ignition key is in the on position. Hope this helps, let me know how you get on.

http://www.autozone.com/autozone/repairinfo/repairguide/repairGuideContent.jsp?partName=Drive+Train&pageId=0900c152801a5958&partId=0900c152801a5958
Here is a link to autozone.com that has step by step instructions a diagrams for that

check your IDLER

it sounds to mee like the brake power booster or abs is acting up.if you dont feel safe driving it use it as a trade in for another vehicle that you feel more comfortable with