It might - there's no way to say for sure. But I have heard some admissions people say that it can raise questions if someone turns in stellar application essays but scores only a 2.0 on the GMAT essay - they may wonder whether the student really wrote the application essays.

Also, sometimes people will just skip the essays and get a zero b/c they think the school doesn't care about the essay score, and I have heard of schools telling those candidates that they'll have to take the test again. Someone who skips the essays would have an advantage on the multiple choice section over someone who completes the essays (because you won't be as tired when you get towards the end of the test).

As frantastic said, you should aim to do "well enough" on the test - ideally a 4.5 or higher but a 4.0 would work, too.