Help! 2003 Santa FE 3.5l won't hold idle
 

Hi Everyone, I'm in need of some advice/help/info and I want to say thanks in advance for any info given!

I've got a 2003 Santa Fe 3.5l V6 w/ fulltime 4WD, 176,000 miles on it. I'm the 2nd owner, the car has been well maintained all of its life. It usually runs very well with an idle that is rock solid smooth at 700 rpm.

Today I was out doing some errands and everything was fine as usual. At my 3rd stop today, I went to start up the car and leave, and while it starts up immediately, the idle doesn't hold. It runs for maybe 3 seconds as the idle doesn't hold and just lets it die. I can put my foot on the gas and it doesn't die, so I'm assuming there's no issue with it getting gas. As long as I have my foot on the pedal, it stays running, and it idles smoothly. It will do it for as long as I want it too, at high or low RPM.

The second I take my foot off the gas, it dies.

I've found other people having issues with this online, but there's never any follow up as to what they did to get it to work, or if they did get it to work. I'm very stuck. I'm unemployed and this is my only transportation. Any insight or ideas would be helpful. If you have had this happen yourself, please tell me what you did to get it to stop.

No engine light, so no codes to get/conditions to read.

Any help is appreciated!

There is a good chance of a vacuum leak where the incoming extra air is not measured and fuel adjustment cannot correct because it is not getting the info of a leak..

Look for a vacuum hose off, cracked or broken.then pinch off hoses to components to see if you can isolate it.

Updating this for the next guy....

My throttle body was super dirty. Cleaning it out with the proper spray took care of the problem.

Thank you for the update.