Exhibit 5.1

April 2, 2015

Board of Directors

Enerpulse Technologies, Inc.

2151 Alamo Ave SE

Albuquerque, NM 87106

To Whom It May Concern:

We act as counsel to Enerpulse Technologies, Inc., a Nevada corporation (the “Company”), in connection with the registration of 22,484,531 shares of the Company’s common stock (the “Shares”) under the Securities Act of 1933, as amended (the “Securities Act”), of which up to: (a) 19,054,688 shares of common stock are issuable upon the conversion of the aggregate principal amount of the senior secured convertible notes issued by the Company on February 20, 2015 to certain accredited investors (the “Convertible Notes”) and (b) 3,429,843 shares of common stock are issuable upon the conversion of interest accrued under the Convertible Notes, and all of which will be sold by the selling stockholders of the Company as defined and further described in the Company’s registration statement on Form S-1 (the “Registration Statement”) filed under the Securities Act.

For the purpose of rendering this opinion, we examined originals or copies of such documents as deemed to be relevant. In conducting our examination, we assumed, without investigation, the genuineness of all signatures, the correctness of all certificates, the authenticity of all documents submitted to us as originals, the conformity to original documents of all documents submitted as certified or photostatic copies, the authenticity of the originals of such copies, and the accuracy and completeness of all records made available to us by the Company. In addition, in rendering this opinion, we assumed that the Shares will be offered in the manner and on the terms identified or referred to in the Registration Statement, including all amendments thereto.

Our opinion is limited solely to matters set forth herein. The law covered by the opinions expressed herein is limited to the Federal Law of the United States and the laws applicable to the State of Nevada.

Based upon and subject to the foregoing, and assuming that (i) the Registration Statement becomes and remains effective, and the Prospectus which is a part of the Registration Statement (the “Prospectus”), and the Prospectus delivery requirements with respect thereto, fulfill all of the requirements of the Securities Act, throughout all periods relevant to the opinion; (ii) all offers and sales of the Shares will be made in compliance with the securities laws of the states having jurisdiction thereof; and (iii) the Convertible Notes and corresponding accrued interest and interest to be accrued under each such applicable note, are converted into Shares pursuant to the terms of such applicable note; we are of the opinion that the Shares to be issued will be legally issued, fully paid and nonassessable.

We hereby consent in writing to the reference to this firm under the caption “Interests of Named Experts and Counsel” in the Prospectus included in the Registration Statement and the use of our opinion as an exhibit to the Registration Statement and any amendment thereto. By giving such consent, we do not thereby admit that we come within the category of persons where consent is required under Section 7 of the Securities Act or the rules and regulations of the Securities and Exchange Commission.

Very truly yours,

/s/ Greenberg Traurig, LLP

Greenberg Traurig, LLP