The Olympic champion, 29, was third overall at the end of a promising first day - traditionally her strongest - with a score of 3,928 points.
On Sunday she leapt a respectable 6.16m in the long jump but threw a disappointing 42.60m in the javelin.
With the 800m remaining, she has 5,544 points, still on course for the 6,200 needed to qualify for the Rio Olympics.
Ennis-Hill is competing in her first heptathlon since winning gold at London 2012.
A top-12 finish and score of 6,075 points would also secure qualification for this summer's World Championships.
Canada's Commonwealth champion and world silver medallist Brianne Theisen-Eaton leads ahead of the final event, remarkably achieving three personal bests on her way to a 5,834 score.
Follow latest updates and reports on the second day of the Gotzis Hypo-Meeting on the BBC Sport website on Sunday, 31 May.
Jessica Ennis-Hill has fallen from fourth to eighth place after six events at the Hypo-Meeting in Gotzis.