This week, the ratings of three auto parts stocks on Portfolio Grader are down. Each of these rates a “D” (“sell”) or “F” overall (“strong sell”).

Fuel Systems Solutions, Inc. (FSYS) earns an F (“strong sell”) this week, moving down from last week’s grade of D (“sell”). Fuel Systems Solutions provides advanced alternative fuel systems technology and components for internal combustion engines. The stock also earns F’s in Portfolio Grader’s specific subcategories of Earnings Growth, Earnings Momentum, Cash Flow and Sales Growth. Shares of the stock are changing hands at twice the rate they were a week ago. To get an in-depth look at FSYS, get Portfolio Grader’s complete analysis of FSYS stock.

BorgWarner (BWA) is on the decline this week, earning a D (“sell”) after receiving a C (“hold”) last week. BorgWarner is a supplier of highly engineered systems and components, mainly for powertrain applications. For more information, get Portfolio Grader’s complete analysis of BWA stock.

This is a rough week for Goodyear Tire & Rubber Company (GT). The company’s rating falls to D from the previous week’s C. Goodyear Tire & Rubber develops, manufactures, distributes, and sells tires and related products and services worldwide. The stock gets F’s in Earnings Momentum and Sales Growth. Trade volume is up 646% from the previous week. To get an in-depth look at GT, get Portfolio Grader’s complete analysis of GT stock.

Louis Navellier’s proprietary Portfolio Grader stock ranking system assesses roughly 5,000 companies every week based on a number of fundamental and quantitative measures. Stocks are given a letter grade based on their results — with A being “strong buy,” and F being “strong sell.” Explore the tool here.