Cost to Fix a Dead Cylinder: Real Repair Prices

💰 The short answer

It ranges from $150 to over $5,000, and a compression test tells you which. The phrase "dead cylinder" describes a symptom, not a part. The real cost to fix a dead cylinder depends on whether the cylinder is electrically dead (no spark or fuel) or mechanically dead (no compression). Electrical and fuel faults are cheap: $150 to $600. Mechanical damage is expensive: $1,200 for a valve job up to $6,000 for a replacement engine. Spend the $100 to $150 on a proper diagnosis before you approve any repair, because the same dashboard misfire light covers all of it.

A "dead" cylinder means one of your engine's cylinders is not contributing power. The engine shakes, runs rough, loses power, and usually throws a misfire code like P0301 (cylinder 1 misfire) through P0308. The fix could be a 30-minute spark plug swap or a complete engine teardown. The only way to know is to test, not guess.

📊 Dead cylinder repair cost by cause

Here is what each common cause actually costs to repair, parts plus labor at a typical independent shop. Dealer prices run 20 to 40 percent higher.

Cause	Type	Typical Cost	Notes
Fouled / failed spark plug	Electrical	$100 - $200	Cheapest fix. Often DIY for $20 in parts.
Bad ignition coil	Electrical	$150 - $400	Most common single cause of a dead cylinder.
Clogged or dead fuel injector	Fuel	$250 - $600	Cleaning is cheaper; replacement varies by engine.
Wiring / connector fault	Electrical	$120 - $500	Diagnostic time is the main cost.
Burned or stuck valve	Mechanical	$1,000 - $2,000	Requires head removal and valve job.
Blown head gasket	Mechanical	$1,200 - $2,500	More on V6/V8 with two heads.
Worn or broken piston rings	Mechanical	$2,500 - $4,000	Engine must come apart.
Cracked piston / scored bore	Mechanical	$3,500 - $6,000+	Usually means rebuild or replacement engine.

Notice the cliff between the electrical group and the mechanical group. Everything above the burned valve line is a same-day repair. Everything below it is a major job. That cliff is exactly what a compression test measures.

🧪 How a compression test sets your price

This is the single most important step, and it costs $100 to $150 at a shop or about $40 for your own gauge. A mechanic threads a pressure gauge into each spark plug hole and cranks the engine. Healthy cylinders read in a tight band.

Normal: 150 to 200 psi, and all cylinders within about 10 percent of each other.
Electrically dead (good news): the dead cylinder reads normal pressure, 150+ psi. Compression is fine, so the problem is spark or fuel. You are looking at a $150 to $600 repair.
Mechanically dead (bad news): the dead cylinder reads 0 to 90 psi while neighbors read 160. The cylinder cannot hold pressure, which points to a valve, head gasket, or piston and ring failure. You are looking at $1,200 and up.

A follow-up "leak-down test" pinpoints where the lost compression is escaping. Air hissing from the exhaust means a burned exhaust valve. Air from the intake means an intake valve. Bubbles in the coolant mean a head gasket. Air from the oil filler or dipstick tube means worn rings or a damaged piston, the most expensive outcome. If you are seeing oil burning too, our guide on blue smoke from the exhaust covers what that adds to the bill.

⚠️ Common mistakes that waste money

Throwing parts at it. The classic mistake is buying a full set of coils and plugs ($300 to $500) before testing, only to find the cylinder has no compression. Test first.
Ignoring the catalytic converter clock. Driving with a dead cylinder pumps unburned fuel into the cat, which can melt it within a few hundred miles. That turns a $200 coil job into a $200 coil plus a $1,200 converter.
Not swapping the coil to confirm. If you suspect a coil, move it to a different cylinder. If the misfire follows the coil, you confirmed a $150 part. If the misfire stays put, the coil is innocent and you saved a wrong purchase.
Approving a rebuild on a high-mileage block. Paying $3,500 to rebuild one cylinder on a 200,000-mile engine often makes less sense than a $2,500 used engine with lower miles.
Skipping the cause of the failure. A burned valve or melted piston usually has a root cause like a lean condition or overheating. Fix the cause or the new parts die the same way.

🧮 Repair it or replace the engine?

Once you know the cause, use a simple value rule to decide. Estimate your car's current market value, then compare the repair quote against it.

Repair vs Car Value	Recommendation
Repair under 30%	Fix it. Easy call, especially for electrical or fuel causes.
Repair 30% to 50%	Usually worth it if the rest of the car is solid and you plan to keep it 2+ years.
Repair 50% to 70%	Compare against a used or remanufactured engine. Often the better buy.
Repair over 70%	Walk away from the repair. Replace the engine or the car.

A remanufactured engine with a warranty typically runs $3,000 to $5,500 installed, while a low-mileage used engine from a salvage yard runs $1,500 to $3,500 installed. Both can beat a one-cylinder rebuild on an older block. If a shop hands you a big number, run it through our repair quote checker before you say yes. It flags padded labor hours and parts markups.

🎯 Your diagnostic game plan

Read the codes. A scan tool pulls the misfire code so you know which cylinder is dead. See our how to read OBD2 codes walkthrough if you have your own scanner.
Swap the coil. Move the suspect coil to another cylinder. Misfire moves with it, you found a $150 fix.
Check the plug. Pull the spark plug. Cracked, oil-soaked, or heavily fouled plugs are cheap and obvious.
Run a compression test. This is the decision point. Normal pressure means a cheap electrical or fuel fix. Low pressure means a major mechanical job.
Leak-down test if compression is low. This tells you valve, gasket, or piston, and therefore the price tier.
Get the value comparison. Compare the final quote to your car's worth before approving anything over $1,500.

❓ Frequently asked questions

How much does it cost to fix a dead cylinder?

It depends entirely on why the cylinder is dead. A bad ignition coil or spark plug runs $150 to $400. A fuel injector is $250 to $600. A burned valve or head gasket job lands between $1,200 and $2,500. A cracked piston, scored bore, or spun bearing usually means a $3,500 to $6,000 rebuild or replacement engine. The diagnosis decides the price.

Can you drive with a dead cylinder?

You can technically limp a short distance, but you should not keep driving. A dead cylinder dumps raw fuel into the exhaust, which overheats and destroys the catalytic converter, a $900 to $2,000 part. Misfire vibration also stresses motor mounts and the rest of the engine. Diagnose it fast.

How do you know if a cylinder is mechanically dead versus electrically dead?

A compression test tells you. If a cylinder reads 0 to 90 psi while the others read 150 to 200 psi, the problem is mechanical: a burned valve, bad head gasket, or damaged piston or rings. If compression is normal but the cylinder still misfires, the dead cylinder is electrical or fuel related, meaning a coil, plug, injector, or wiring fault.

Is it worth fixing a dead cylinder or should I replace the engine?

If the cause is a coil, plug, injector, or even a head gasket, repair is almost always worth it. If a cylinder has mechanical damage and the repair quote approaches 50 to 70 percent of the car's value, a used or remanufactured engine often makes more sense than a rebuild on an old block.

What is the cheapest dead cylinder repair?

The cheapest fix is a fouled or failed spark plug, often $20 in parts and 30 minutes of labor, or about $100 to $200 at a shop. A failed ignition coil is the next cheapest at $150 to $400 installed. These two account for a large share of dead cylinder complaints.

✅ TL;DR

"Dead cylinder" is a symptom; the cause sets the price.
Cheap causes (plug, coil, injector, wiring): $100 to $600.
Expensive causes (valve, head gasket, piston, rings): $1,200 to $6,000+.
A $100 to $150 compression test sorts cheap from expensive before you approve anything.
Do not keep driving; you risk a $1,200 catalytic converter on top.
If a mechanical repair tops 50 to 70 percent of car value, look at a replacement engine instead.

Cost to Fix a Dead Cylinder: From a $150 Coil to a $5,000 Engine