Blown Head Gasket: Fix It or Junk the Car?

None of these proves it alone, and other problems can look similar. They are a reason to get it tested soon.

• Coolant level keeps dropping with no puddle under the car.
• White smoke from the tailpipe that smells sweet.
• Milky or foamy oil on the dipstick or inside the oil cap.
• Bubbles in the coolant reservoir with the engine running.
• Overheating, especially on hills or in traffic.
• Rough running or misfires, sometimes worst right after a cold start.

If you see these, stop driving the car. Coolant in the oil harms bearings, and a hot engine can warp metal. Each trip can turn a gasket job into an engine job. Have it towed.

Ask which of these tests was done. A shop that has tested can show you what it found:

This matters because simpler failures, like a water pump, radiator or thermostat, can cause some of the same symptoms. Those are different decisions.

The gasket may not be the expensive part. Your decision depends on what the failure did to the engine around it. Ask the mechanic these questions before approving the job:

• How hot did it get, and how many times? Be honest about any warning light you drove through.
• Will the cylinder head be sent to a machine shop to be checked for warping and cracks? Is that in the quote?
• What happens to the price if the head or block is cracked?
• Has coolant reached the oil? Will the bearings need to be checked?
• Does this engine have a known weakness that could make the new gasket fail too?
• Is the timing belt or chain, water pump or thermostat worth replacing while it is apart?
• What is the warranty on the work, in writing?

You will see sealers at any parts store. Ask your mechanic about them before you pour one in. A sealer does not repair a warped head or a bad gasket in any lasting way, and some can clog parts of the cooling system. It also does not make an overheating car safe to depend on.

If you are planning to sell, do not use a sealer to hide the problem from a buyer. Tell them what the car is doing.

Use real numbers for that value line. Our value guide shows how to get them, and the repair or junk guide shows how to compare them. If the engine is beyond this repair, read about a blown engine.

Because the car should not be driven, plan on a tow. A private buyer may want it as a project, as long as you tell them it needs a head gasket. Otherwise, we buy cars with this problem as they are. Non-running cars are fine, the flatbed tow is free, and we pay cash at pickup. If it has been leaking, read what to do about a leaking car before pickup.