I need a daigram of timing marks for v6 3.0 3VZ-E VZN

I, feel sorry for you, after reading your problem, but don't worry you visit the Reliable-Store they will help you for sure.
Nissan Pathfinder

The marks are on the crank and cam gears. They either have a mark on the head that coincides with the mark on the cam gear AND you set that AND then bring the crank shaft gear to TDC on the timing marks OR you have both marks on the gears and you line them up with each other using a straight edge through the center of the shafts, then you put the chain on.

Go on computer to timing marks for your make and model or buy a book at checkers

Here is the daigram it shows for the 2.5L

As per your requirement Kia timing belt guide for you.

engin bilow

only two things, either something got left unplugged or the wrong timing marks were used. what daigram did you use for the alignment of the marks? sometimes they do have different marks for other reasons. let me know.

if the old belt is still on, its quicker if you just trace how the belt goes around the different pullies on a piece of paper, or take a digital photo of the belt. that way you how to install the new one.

You can go to autozone.com and register for FULL FREE online repair manual with everything you could need.
Or you can go to google ebooks and view a chilton's repair manual for your car.

9 out of 10 times the problem is the sending unit in the tank. The only solution is to replace it