Investing in used engine for sale may be the most cost-effective solution to getting your vehicle back on the road quickly. However, if you acquire a pre-owned engine from a shady salvage yard or pick one at random off of Craigslist, you run the risk of your predicament being much more dire than it was before. The cost to replace a stadard gasoline engine with a brand-new engine is anywhere from $4,500 to $6,000 on average. Evenn a used engine may cost you between $3,000 and $4,000, depending on its condition.