How much does it cost to replace an engine?

How does a car engine work?

Put simply, an internal combustion engine (the kind in most automobiles) combines fuel, air and spark to produce a series of small, controlled explosions. These small explosions are contained within the cylinders of your vehicle's engine, and each time the explosion occurs, a piston in the cylinder is driven up and down. These pistons are connected to a crankshaft, which is in turn connected to the vehicle's transmission and from there to the rest of your drivetrain.

This process repeats itself thousands of times a minute while your car is running, with various engine components and systems working in harmony to propel your vehicle down the road. However, should one of these components fail, it can cause a domino effect that can damage and even ruin your engine.

For example: If you have a failing gasket, your engine will slowly lose oil. Over time, the amount of oil in your engine is significantly reduced, and this lack of lubrication can lead to the internal components of your engine heating up past their design thresholds. Left untreated, this overheating can cause everything from warping to major engine damage.

Symptoms of engine failure

Because your engine is so integral to your car’s functions, engine failure can affect many different systems and show itself in many different ways. Still, there are several common symptoms that you should look out for if you think your engine is failing:

• Check engine light: Most modern vehicles utilize a check engine light to let you know that one of the engine’s many sensors has detected a problem. This could be a small issue (like a loose gas cap) or a major one, like engine failure. The only way to know what caused the check engine light to come on is to have the system scanned with an OBD-II code reader.
• Decreased performance: This can mean a lot of different things, from decreased fuel efficiency to failure to move your car at all. If your engine is running rough or not behaving normally, it’s a good idea to get it checked out.
• Knocking: One of the most common symptoms of engine failure is a knocking or thumping noise coming from your engine bay. A similar sound can be caused by fuel burning unevenly in a cylinder, but one more serious cause is a failing engine bearing.
• Grinding: Grinding noises can come from a lack of lubrication between critical engine components that has resulted in metal-to-metal contact.
• Increased exhaust: A sudden increase in the amount of exhaust your engine is producing usually means something is burning that shouldn’t be. You may be able to tell what’s burning by the color of the new smoke.
  • Black smoke is a sign that too much fuel is making it into the engine.
  • Blue smoke generally comes from burning engine oil.
  • White smoke comes from burning antifreeze or coolant.
• Oil or coolant leaks: Oil or coolant spots on the ground under your vehicle could be a sign of engine failure. If a leak is caught early enough, it may not be an issue, but if your car has been leaking for months, the lack of fluids may create other problems.

If you suspect you have major engine issues, visit a mechanic you trust to find out exactly what you're dealing with. Qualified mechanics will run a full diagnostic scan on your vehicle and perform a thorough visual inspection to determine what the cause of your problems is. If your mechanic tells you that your engine is seriously compromised, you'll generally be presented with two options: an engine rebuild or an engine replacement.

How much does it cost to rebuild an engine?

In general, engine rebuilds are less expensive than engine replacements. Costs vary widely depending on the type of engine you have and how much work it needs, but an average price is anywhere from $2,500 to $4,000, according to the National Automobile Dealers Association (NADA).

If you elect for a rebuild, your mechanic will disassemble your vehicle's engine, inspect the damaged components and reassemble the engine with new or re-machined parts to replace whatever was causing the issue. There are a lot of intricate processes involved in a rebuild, but by the end your engine should be back in working order and nearly good as new.

On the downside, this process can take up to two weeks, and it can have a drastic effect on resale value since many people don't want to purchase a vehicle with a rebuilt engine. While this mentality isn't necessarily fair, it is often a reality.

How much does it cost to replace an engine?

If you choose to install a replacement, your mechanic will purchase another engine and swap it out for your old one. Engine prices vary so significantly from manufacturer to manufacturer that it’s hard to pinpoint prices, but your mechanic should provide you with an itemized quote showing the cost of the replacement engine and what they’re charging for labor.

If you’re buying a new crate engine from the factory and having it installed at the dealership, expect to spend anywhere from $4,000 for a four-cylinder engine to upwards of $10,000 for a high-performance engine. However, most prices are somewhere in the middle, and buying new isn’t your only option.

If you want to save money, you can find a cheaper mechanic and have them install a remanufactured or salvaged engine instead:

• Remanufactured engines have gone through a more stringent rebuild process to make them almost as good as a newly built engine, and some even come with warranties. Again, costs will differ, but installing a remanufactured engine will often split the difference between the cost of a rebuild and installing a crate engine.
• Salvaged engines are pulled from used vehicles in junkyards. They are often the cheapest option in this scenario (with some engines costing only a few hundred dollars), but they might have other issues from previous use or neglect.

You can theoretically get your new engine from almost any vehicle or maker, but replacing your engine with something different may require more time and money. One possible exception is if your automaker uses the same family of engines across multiple vehicles, like with Chevrolet’s LS series of engines found in many of the company’s trucks, SUVs and performance cars.

Different engines in the same family will have different characteristics, but swapping them is often easier than replacing one with something outside the engine family. However, it’s still generally easiest to replace your engine with an identical model.

Warranty coverage

If your engine is covered by a warranty, then the cost to rebuild or replace it may be negligible. Your engine is a part of your vehicle’s powertrain, which means it’s covered for a certain amount of time or miles by most factory warranties and extended warranties. To see if your engine is still under warranty, check with the manufacturer or your extended auto warranty provider.

How long does it take to replace an engine?

In terms of labor, an engine replacement can take your mechanic anywhere from eight to 20 hours, depending on your vehicle. At a rate of $100 per hour, this means you could spend $800 to $2,000 on labor alone, and some mechanics charge even higher rates. In 2017, AAA found that repair shops in its network charged between $47 and $215 per hour.

Replacing an engine is a considerable undertaking, and you may be without your vehicle even longer than the time your mechanic actually spends working on it. Time spent sourcing a new engine, replacing your old one and testing the replacement generally means anywhere from three days to a week in the shop — maybe longer.

Is it worth rebuilding or replacing an engine?

Given the high costs of rebuilding or replacing an engine, there’s a certain point where they no longer make financial sense. In some cases, it’s more cost-effective to junk your car and buy a new one rather than fixing it.

If you’re unsure whether a rebuild or replacement is worth it, think of your repair bill in terms of the value you’re getting back. Try to do the math on how many years of driving you'll get out of your car once it’s fixed and how much you can sell it for when you’re done with it.

1. How long do you plan to keep your car? If your car’s other components are wearing out, spending a lot of money on the engine might not guarantee much more time on the road. You should also factor your plans into which repair option you choose. A salvaged engine generally won’t have as many miles left as an OEM (original equipment manufacturer), remanufactured or rebuilt engine. If you plan to sell the vehicle immediately, a replaced OEM engine will almost always fetch more money than a rebuilt one.
2. How much is your car worth? If your vehicle is only worth $3,000 in good condition and it's going to cost $4,000 to replace the engine, you may be better off writing your vehicle off as a loss. However, if your vehicle is worth $30,000 and it's going to cost the same $4,000 to fix, replacing the engine may be a better choice.

Bottom line

While replacing or rebuilding an engine is expensive, it can be critical to keeping your car on the road. Check with your mechanic to see which options they recommend, and decide for yourself whether it’s worth fixing the problem or just getting a new car.

If you’re concerned about the engine going out on your next vehicle, consider an extended warranty to help cover the costs.