I picked up a 2006 Sante Fe with the 3.5 for my daughter for college and it has been a nightmare's getting this car running properly. I think I have most of the bugs worked out but this one is back and very consistent now. When you go to start the car it will not start and if you continue to turn the key it just floods the engine. Pull the fuel pump relay till it start and then just plug the relay in and it will run just fine. Some times it starts but lately its almost everytime. I have a basic hand scanner so is there anything in the live data that I should be looking at prior to trying to start it? i think it has the fuel trim numbers. I did see engine temp and it appears to be reading correctly. I haven't checked compression but engine runs great once its running so didnt think that would be an issue. I haven't changed the timing belt yet, 145k so I know its due but i don't think it would stretch so far that it would throw timing off enough to effect the start but I'm open to anything right now.

 

When it won't start, remove a spark plug or two.
See what they look like, if wet , extra fuel is getting into the engine. A problem with the throttle position sensor connections could be involved.
The engine does have a clear flood mode available. If the throttle pedal is held to the floor while cranking it should allow the extra fuel to be cleared out so the engine can start.
What ever is causing the problem can be narrowed down to which and how many plugs are soaked with fuel.
Post the results here , may be able to offer some help.

 

I thought I had a leaking/stuck injector so I replaced the injectors.....no change. new fuel pump assy with pressure regulator...no change. When I pull the plugs they all have the same amount of wetness/fouling.

i did have to replace the TPS sensor as well as the throttle pedal sensor. Would an incorrect adjusted TPS sensor throw the start sequence out of whack? My scanner doesn't have the option to see voltage at the sensor to adjust it.

 

Unless you received defective parts, i don't believe we have a fuel problem.

When it won't start do you know how to check for spark?

When cranking to start, did you notice if the RPM gauge showed any RPMs?

 

I havent checked for spark when it won't start but I assume it does because when I pull the fuel relay it will start. I'm still going to check when it won't start just to make sure.

Yes, the tach will move and you will also see RPM on the scan tool. I thoght it could have been the crank sensor dropping out but I do get RPM unless the Cam sensor is the issue? What should the timing be on initial start? I think the scanner show 5* BTDC. Could it be something as stupid as needing plugs? Runs amazing once it's started

 

I think I got it fixed! Yesterday when it wouldn't start, I noticed that the temp sensor was was at -9* and it would go to normal temp then go back to some negative number. I replaced the temp sensor and so far it has started every time.

 

Good point, thank you for the update and sharing the fix with us.