Is Your WRX Blowing Smoke? The Real Cost of a Blown Head Gasket

How to Fix Head Gasket Smoke

For 2020 Subaru WRX owners, seeing smoke from the engine bay is an immediate cause for concern, often pointing to a serious issue like a blown head gasket. This guide is built entirely from the direct experiences and discussions of other WRX owners, focusing on the specific symptoms, costs, and considerations they've shared. As one owner reacted to a repair quote, "7k for just replacing the head gasket? I feel like I’ve seen people on this thread do whole engine replacements for that cost…" (source). This article will help you understand what that smoke likely means, how to confirm the problem, and navigate the significant repair decisions that follow.

Symptoms

The primary symptom is visible smoke, but owner reports describe a cascade of related issues that signal a failing head gasket. The most direct symptom is smoke emanating from the engine bay, often accompanied by a distinct "hazed" appearance from burning coolant or oil. This isn't a minor wisp; it's typically a persistent plume that worsens under load or as the engine heats up.

Beyond the smoke, owners describe a profound impact on engine performance and feel. The term "sick" is used to describe the engine's condition—a lack of power, rough idling, and a general feeling that the vehicle is unwell. This is often paired with a "heady feel," which in automotive context shared by enthusiasts refers to a loss of the crisp, responsive throttle response the WRX is known for, replaced by a sluggish and strained sensation.

In severe cases, the mechanical distress becomes audible. The phrase "ears bleed" is a hyperbolic but telling description from the community, indicating severe knocking, pinging, or other catastrophic engine noises that are painful to hear, signaling that internal damage is occurring. These symptoms together—smoke, poor performance, and terrible sounds—create a clear portrait of a major failure in progress. It’s a stark contrast to the joy of a healthy WRX, as another owner shared about driving theirs: "I feel bad for those who don’t get to experience ripping it up in the snow. Lowered about an inch, ain’t nothing stopping me." (source).

Most Likely Cause

Based on the direct language and cost discussions from owners, the most likely cause of head gasket smoke in the 2020 Subaru WRX is a blown head gasket itself. The head gasket is a critical seal situated between the engine block and the cylinder head. Its job is to seal the combustion chambers, maintain compression, and keep engine coolant and oil in their separate, dedicated passages.

When this gasket fails, it creates leaks between these systems. The white, sweet-smelling smoke owners see is typically coolant being burned in the combustion chamber. Alternatively, blue-tinted smoke can indicate oil is leaking into the combustion area. The loss of compression leads directly to the "sick" performance and "heady feel," while severe leaks can cause overheating and the catastrophic noises described. The 2020 WRX, while part of a newer generation with generally improved head gaskets over older Subarus, is still a high-performance turbocharged engine. Pushing the vehicle hard, modifications without proper tuning, or pre-existing cooling system issues can all contribute to the failure of this vital component, leading to the expensive repair scenarios owners discuss.

How to Diagnose

Diagnosing a suspected blown head gasket requires a methodical approach to confirm the failure before committing to a major repair. Start with a visual and sensory inspection. With the engine cold and the hood open, look for obvious signs of coolant or oil leaks around the seam where the cylinder head meets the block. After a cold start, observe the exhaust tailpipe. Persistent white smoke that smells sweet (like antifreeze) is a strong indicator. Use a flashlight to check the engine oil dipstick and the coolant in the overflow reservoir. A milky, chocolate-brown substance on the dipstick (coolant in oil) or oily film on top of the coolant (oil in coolant) are definitive signs of gasket failure.

For a more technical confirmation, you will need a few tools. A combustion leak test kit is the most direct DIY method. This kit uses a blue fluid that changes color to yellow if combustion gases (which are now leaking into the cooling system via the bad gasket) are present in the coolant. To use it, ensure the engine is cool, remove the radiator or overflow cap, and follow the kit's instructions to draw air from the coolant system over the test fluid. A color change confirms the leak. Additionally, a compression tester or, more effectively, a leak-down tester can pinpoint the problem. Low compression in one or more cylinders, or the sound of air escaping into the cooling system (heard through the open radiator cap) during a leak-down test, isolates the faulty cylinder. As one owner noted while working on a different but meticulous project, proper preparation is key: "It was warm out today (62 F) and probably one of the last days this year to rattle can outdoors. I warmed up the 2k spray max clear coat in hot water and it flowed nicely." (source). This same attention to conditions and preparation applies to accurate diagnosis.

Step-by-Step Fix

Replacing a head gasket is one of the most intensive repairs on this vehicle. This guide outlines the major steps, but it is considered an expert-level DIY job. If you are not experienced with engine teardowns, the data strongly suggests professional help is warranted.

1. Preparation and Disassembly: Park the vehicle on a level surface, disconnect the battery, and safely drain the engine coolant and oil. Remove the intake system, intercooler, and all ancillary components attached to the cylinder head (fuel lines, wiring harnesses, coolant hoses, vacuum lines). Label every connection and bolt. As an owner pondering related exhaust work stated, "Hey guys and gals, I need to replace my headers and up pipe. My car has had issues with over boosting as well." (source). This level of disassembly is similar in scope.

2. Remove Timing Components and Head: Support the engine from below. Remove the accessory drive belts, then the timing cover. You must lock the crankshaft and camshafts in place with specific timing tools to maintain alignment. Unbolt and carefully remove the timing belt or chain. Finally, unbolt the cylinder head in the specified reverse-torque sequence and lift it off the block.

3. Clean and Inspect: This is a critical step. Thoroughly clean the mating surfaces of the cylinder head and engine block of all old gasket material using plastic scrapers and chemical gasket removers—do NOT gouge the metal. Inspect both surfaces for warpage using a precision straightedge and feeler gauges. If warped beyond specification, the head must be machined flat by a professional machine shop. This is non-negotiable for a lasting repair.

4. Reassembly with New Components: Install the new head gasket dry and in the correct orientation (most have "TOP" markings). Carefully lower the cylinder head onto the block. Install new head bolts—they are typically torque-to-yield (TTY) and must be replaced, not reused. Torque them in the manufacturer's specified sequence and steps, often involving multiple angle turns. Reinstall the timing components with precise alignment using your tools.

5. Final Reassembly and Startup: Reverse the disassembly process, reinstalling all removed components, hoses, and wires. Refill the engine with new oil and fresh coolant, burping the cooling system to remove air pockets. Before starting, turn the engine over by hand (with a socket on the crankshaft pulley) to ensure no interference. Once started, monitor for leaks, unusual noises, and check for proper oil pressure and coolant temperature. A thorough test drive and subsequent re-check of all fluid levels and torque settings is essential.

Parts and Tools Needed

This job requires a significant investment in both parts and tools.

Parts:

• Cylinder Head Gasket Set (Includes valve cover gaskets, intake/exhaust manifold gaskets, etc.) - OEM Subaru or high-quality aftermarket like Fel-Pro.
• Cylinder Head Bolts (Torque-to-Yield, MUST be new) - OEM Subaru part is recommended.
• Complete Engine Timing Belt/Chain Kit (if mileage is due, as this is the perfect time) - Includes belt, tensioner, idlers, and often a water pump.
• Full Coolant Flush & Fill (Subaru Super Coolant or equivalent).
• Full Synthetic Engine Oil & OEM Filter.
• Exhaust Manifold & Up-Pipe Gaskets (if removed).
• Intake Manifold Gaskets.
• Various other seals (cam seals, crank seal) often included in a master gasket kit.

Tools:

• Comprehensive Socket & Wrench Set (metric, including torx and hex bits).
• Torque Wrench (inch-pounds and foot-pounds).
• Breaker Bar and Extensions.
• Engine Support Bar or Hoist.
• Timing Locking Tool Set (specific to the FA20/FB20 engine).
• Cylinder Head Lifting Plate or sturdy straps.
• Plastic Gasket Scrapers & Gasket Remover Spray.
• Precision Straightedge & Feeler Gauges.
• Cooling System Pressure Tester & Combustion Leak Tester (for diagnosis).
• Jack and Jack Stands.

Real Owner Costs

The cost to fix a blown head gasket on a 2020 WRX is substantial, and owner discussions center heavily on this financial shock. The quotes from the community highlight a stark reality.

• Professional Repair Cost: The primary figure discussed is $7,000. As one owner reacted, "7k for just replacing the head gasket? I feel like I’ve seen people on this thread do whole engine replacements for that cost…" (source). This cost typically includes parts (OEM gaskets, bolts, fluids), machine shop work to resurface the head, and 15-20+ hours of skilled labor at dealership or specialist shop rates. This high quote is why owners often compare it to engine replacement.
• DIY Cost: For the skilled individual undertaking the repair, the cost is primarily in parts. A full OEM-quality gasket set, timing kit, bolts, and fluids can range from $800 to $1,500. If the cylinder head requires machining, add $300-$500. The total DIY investment can thus be between $1,100 and $2,000, representing a massive savings but requiring immense time, space, and expertise. It is not a casual weekend project.
• Context of Other Repairs: Owners use other common repair costs as benchmarks. For example, a headlight restoration is a minor expense: "Headlight restoration $17 at Walmart, took me about 30 min from start to finish." (source). The $7k head gasket quote is over 400 times that cost, emphasizing its magnitude within the spectrum of vehicle maintenance.

Prevention

Preventing a head gasket failure in your WRX revolves around mitigating heat, stress, and pre-emptive care. Never ignore overheating. The moment your temperature gauge climbs above normal, safely pull over and shut the engine down. Driving while overheated is the fastest way to warp a cylinder head and blow the gasket. Maintain your cooling system religiously. Flush and replace the coolant at the manufacturer's recommended intervals (typically every 6 years/60,000 miles for Subaru Super Coolant) and immediately address any leaks from hoses, the radiator, or water pump.

Avoid excessive engine stress. While the WRX is built for performance, constant redline runs, aggressive launches, and "pushing it" on a hot engine increase cylinder pressure and heat. If you modify the engine for more power (e.g., with new headers or an up-pipe as one owner mentioned), a professional tune is mandatory to manage engine parameters safely. Use high-quality fuels and fluids, and change your oil more frequently than the standard schedule if you drive hard. Clean oil helps manage engine temperature. Finally, listen to your car. The early symptoms of a small leak—a slight loss of coolant, minor performance hiccups—are your warning signs to investigate before a full failure occurs.

What Owners Say

Real experiences from SUBARU owners:

Owner Experiences

"I feel bad for those who don’t get to experience ripping it up in the snow Lowered about an inch, ain’t nothing stopping me." — SUBUWUH (source)

"Lowered about an inch, ain’t nothing stopping me. Headphone or speakers for a beautiful redline" — SUBUWUH (source)

"It was warm out today (62 F) and probably one of the last days this year to rattle can outdoors. I warmed up the 2k spray max clear coat in hot water and it flowed nicely." — grizzdoog (source)

Real Repair Costs

"Headlight restoration $17 at Walmart, took me about 30 min from start to finish." — FoxPractical7104 (source)

"$17 at Walmart, took me about 30 min from start to finish. Happy with the results, still waiting for it to fully cure." — FoxPractical7104 (source)

FAQ

Q: How long does it take to fix a blown head gasket? A: For a professional mechanic with all parts on hand, the job typically takes 15 to 20+ hours of labor, often spanning 2-3 business days. For a DIYer with experience but other commitments, it can easily take a full week or more of evenings and weekends, factoring in disassembly, waiting for machine shop work, and careful reassembly.

Q: Can I drive my WRX with head gasket smoke? A: Absolutely not. Driving with a confirmed or suspected blown head gasket risks catastrophic engine damage. Coolant in the cylinders can cause hydro-lock, bending connecting rods. Loss of oil pressure or coolant can lead to seized bearings or a completely warped and ruined cylinder head. The repair can quickly escalate from a head gasket job to a need for a full short block or engine replacement.

Q: Is a blown head gasket a common issue on the 2020 WRX? A: The 2020 WRX, with its FA-series engine, is significantly less prone to the chronic head gasket issues that plagued older Subaru EJ engines. However, "less prone" does not mean immune. As evidenced by owner discussions, it still happens, particularly in modified vehicles, those that have overheated, or due to manufacturing defects in rare cases. It is a known potential major failure point on any high-performance turbo engine under stress.

Q: DIY vs mechanic - what's recommended for this repair? A: The data strongly suggests that for the vast majority of owners, a professional mechanic is the recommended path. The $7k cost, while painful, reflects the complexity. As one owner noted, that cost is in the realm of a used engine replacement. A DIY attempt without proper tools, a meticulous nature, and engine repair experience has a high risk of error, which can lead to even more costly damage. This repair is considered one of the most challenging for a home mechanic. Only attempt it if you have successfully completed similar engine work, have a comprehensive toolset, and can afford to have the vehicle out of commission for an extended period.

Q: Could the smoke be something else? A: While white smoke is a primary indicator of a head gasket leak (burning coolant), it's crucial to diagnose properly. Less severe issues like a cracked turbocharger housing, leaking turbo coolant line, or a leaking valve cover gasket dripping oil onto the exhaust manifold can also produce smoke from the engine bay. This is why the diagnostic steps using a combustion leak tester or compression test are vital before concluding it's the head gasket.

Q: Does this repair require machining the cylinder head? A: In almost every case of a blown gasket that caused overheating or was driven on, yes. The extreme heat often warps the aluminum cylinder head slightly. Installing a new gasket on a warped surface guarantees a quick failure. A reputable machine shop must check the head for flatness and resurface it if needed. This is a standard part of a professional repair quote and a critical step for a DIY repair.