Subaru WRX knocking problems

Filed Oct 2, 2026 · Engine · CO

On June 24, 2026, my stock 2018 Subaru WRX Limited experienced a sudden catastrophic internal engine failure at approximately 67,319 miles while I was driving. I first heard an intermittent ticking/noise under acceleration. Within about two miles, the noise became much louder, followed by a loud pop, sudden loss of power, and smoke from the engine bay. I was able to get the vehicle stopped safely. I do not recall a warning light or message before the failure. The vehicle was towed to an authorized Subaru dealer. A full engine teardown found catastrophic internal damage concentrated in cylinders/rod bearings 2 and 3, including multiple holes in the engine block, while cylinders 1 and 4 were comparatively intact. The service advisor stated that the damage pattern did not appear consistent with generalized lack of oil and that recent over-revving was not indicated by the vehicle data. An independent inspection on September 17, 2026 confirmed catastrophic internal material failure involving cylinders 2 and 3, crankshaft damage, a deeply gouged cylinder wall, and metal debris associated with the failure. The inspector found no modifications, abuse, commercial use, or outside influence. This sudden loss of engine power and smoke while driving created a safety risk because the vehicle could no longer maintain normal power in traffic and there was concern about further mechanical damage or fire. The failed engine and disassembled components remain available for inspection, along with dealer teardown records, photographs, and the independent inspection report. The vehicle was stock and serviced through authorized Subaru dealerships. The exact initiating cause of the failure remains undetermined.

Filed Apr 6, 2026 · OR

Complaint Summary: I am filing a complaint regarding a potentially defective A/C compressor that is producing abnormal noise and may indicate premature failure. Description of Issue: My vehicle’s A/C compressor produces a loud, rhythmic “chugging” or knocking noise at idle when the A/C system is off. The noise is excessive and not consistent with normal operation. When the A/C is turned on, the noise changes but remains abnormally loud. Based on my experience and comparison to other similar vehicles, this is not normal behavior. A comparable 2024 Subaru WRX does not exhibit this issue, and many other 2022 WRX owners have reported similar symptoms. Safety Concern: This is not just a noise concern—it may indicate internal compressor failure or premature wear. The A/C compressor in this vehicle is part of a continuously driven system (no traditional clutch), meaning it is always engaged via the serpentine belt. If the compressor were to fail internally, it could: •Seize or bind, potentially damaging or breaking the serpentine belt •Lead to sudden loss of power steering assist (if belt-driven) •Cause loss of alternator function (battery charging failure) •Result in engine overheating if the water pump is belt-driven •Leave the vehicle stranded unexpectedly This presents a potential safety risk, especially if failure occurs while driving. Additional Context: Subaru has issued a Technical Service Bulletin (TSB) for a similar A/C compressor issue in another model using a comparable design, which includes replacement procedures for certain serial number ranges. Despite this, Subaru has not acknowledged the issue for the WRX, even though there are numerous owner reports of the same symptoms. Conclusion: The abnormal noise suggests a potential defect that could lead to premature failure and safety-related consequences. I am requesting that this issue be investigated for possible defects in design or manufacturing affecting the A/C compressor in the 2022 Subar

Filed Sep 23, 2024 · Engine · NY

I purchased the vehicle used with 33800 miles and at 34100 the engine stalled and was hard to start, once started it was knocking severely. I have seen a class action law suit based on the same issues but the 2020 model year is not included

Filed Sep 6, 2024 · Engine · WI

With 61,700 miles on the car the engine lost a rod bearing going around a sharp corner on and off ramp of interstate highway. If failure had caused block to crack or break it would have put oil down on the highway and would of caused loss of control of the car. From research done online it seems sharp corners cause engine catastrophic failure. Car is currently at Subaru dealership. Subaru will not do anything about the issue. Vehicle had fresh oil change 2 days before failure with no noise or warning before failure.

Filed Jul 27, 2024 · Engine · AR

I bought a 2018 Subaru WRX with 61,000 miles, After driving it 6,000 miles with engine spun a rod bearing, requiring a complete engine replacement. This is a vehicle that in the previous 4th generation of the car, it was recalled for this exact issue. the total repair bill for this fix is $11,720.43. This is on a car with 67,000 miles. 7,000 miles over Subaru's manufacture warranty. After speaking with a few service advisors at Subaru. it is my belief, that this is a known issue with this model.

Filed Mar 27, 2024 · Engine · WA

Engine rod knock at 32,000 miles due to bearing failure causing loss of control of vehicle and sudden loss of power and control. Car was logged to be traveling at 35 mph with normal acceleration at time of failure. Carter Subaru confirmed bearing failure, and fits with the pattern confirmed in 2012-2017 WRX STi engine failure class action settlement, as part in 2018 remains unchanged from 2017 according to mechanics. Head mechanic at dealership confirmed that only car modification (intake) would not cause catastrophic loss of oil leading to bearing failure, and thus it is likely due to engine design that leads to poor oil circulation as a known issue in this EJ25 engine type. Engine components have been inspected by Carter Subaru, and have been made available to Subaru of America, along with images, videos, pictures, receipts, logs, records, computer/ECU data, receipts, tool purchases, and other maintenance and service logs for the car (including prior to ownership). Dealership acknowledges that the car maintenance exceeded the manufacturer recommendation, yet engine still failed even with oil changes done at 3,000 mile intervals... While manual states much higher interval to follow. Engine still failed at increased oil change levels. Problem appeared once engine started knocking, which means the engine has already suffered irreversible engine failure and needs to be replaced, according to Subaru. Subaru of America assigned a customer advocate but has been incommunicado for the duration of the investigation and refuses to answer or even acknowledge that a claim has been opened, as they constantly cite erroneous interactions with the vehicle owner.

Filed Mar 7, 2024 · Engine, Transmission · GA

Severe engine failure! Was driving steady speed on highway, then I let off the throttle and heard a bad knocking noise on deceleration. The engine oil temp increased to around 230F. I slowed down to limp it to the next exit and it started jerking. I made it to an exit and the engine stalled at the red light. No smoke, oil level good, coolant level good. Had it towed to Subaru dealer, where they said the engine has severe damage and needs a Short Block Engine Assembly. Warranty was denied because it has a cold air intake. Complained to Subaru Corporate because an intake should not cause catastrophic engine failure at only 38,000 miles.

Filed Jan 8, 2024 · Engine · TX

Engine Failure rod bearing failure is extremely common. Can leave motorist in danger being stranded on the road. Subaru of America has inspected the engine but claims they are at not fault and refuse to assist. Investigate online how common the motor failure on a fa20dit motor is. I can tell you many owners who are on their 2nd to 3rd motor. This is extremely dangerous and I hope there is a resolution.

Filed Apr 10, 2023 · Engine, Fuel system · NY

I purchased a 2016 subaru wrx (premium) used from a subaru dealer in albany, ny with under 26k miles for approximately $25k in 2018. On a drive in december 2022 I experienced hesitation and/or stuttering under load or when attempting to accelerate, and car began getting very hot, and close to overheating, and the engine was knocking loudly. After turning engine off and then restarting, the knocking (intensity) was not as noticeable as the initial incident. Initially I replaced all coil over plugs, as cylinder #4 initially was reporting a misfire code after the check engine light came on. This appeared to relieve the misfire briefly, but the issue immediately returned, this time with piston #3 reporting misfires and also exhibiting signs of a possible failed ringland, with oil seeping past rings (on to / in spark plug) causing the engine to run very poorly. Presently upon startup white smoke comes from exhaust out the tailpipe and the engine is hesitating and/or missing, running poorly and I feel it cannot be driven safely with the diminished permormance or complete lack of ability to accelerate normally like a motor vehicle should. I have engaged a mechanic to inspect the engine, but have not yet proceeded with inspection/repairs due to the class action litigation. Current mileage is: 73563. This car has an fa20 engine.

Filed Mar 21, 2023 · Engine · WI

Engine has rod knock present common amongst owners. Short block replaced under warranty at 55k miles. How can a stock engine with synthetic oil changes commonly fail? Flaws.