Subaru Legacy knocking problems

Filed Jun 4, 2026 · Engine · CT

Vehicle: 2021 Subaru Legacy Base 2.5i Mileage:~65,000 miles My engine suddenly began making loud internal knocking/tapping noises with no warning lights, no overheating, and no prior symptoms. The vehicle immediately became unsafe to operate. I had it towed to a Subaru dealership, where technicians confirmed the noise was coming from inside the engine and recommended a full engine replacement. The failure happened without any warning indicators, misfires, overheating, or oil pressure warnings. All diagnostics (including compression and leakdown) were clean, and the vehicle has been properly maintained. Subaru of America acknowledged the internal failure but only offered $1,000 goodwill toward a multi‑thousand‑dollar engine replacement. This appears to be a premature internal engine failure on the FB25 engine, which may indicate a defect. A sudden internal engine failure at highway speeds could lead to loss of power, stalling, or inability to accelerate, creating a safety hazard for the driver and surrounding traffic. I am filing this complaint because this type of unexpected internal engine failure at relatively low mileage may represent a pattern and should be tracked for potential investigation.

Filed Mar 17, 2025 · Driver assistance · MO

purchased my 2016 legacy in 2022, I was offered the bronze warranty due to milage. My vehicle was bought back due to loud noises coming from the engine. Was told there was a peze recall and it was fixed. Brought it back to the dealership for the same sound and they found nothing wrong. A few weeks later leaving work, I noticed my muffler was hanging. I took it to a local muffler shop where the repaired it and repaired the heat shield which was loose and knocking up against the exhaust. Still taking my vehicle to the dealership for the warranty clear coat/ zetec and was told that I needed two-wheel bearings and that I was over milage, that it wouldn't be covered. I had both wheel bearing replaced and rear brakes within the first year of having the vehicle. Later part of 2024 my dashboard was lighting up, not allowing any of my safety features to work and I have no traction in the snow. I took the vehicle back to the dealership where I was told that it had a bad valve body, That the vehicle was over the milage for the extended warranty repair. I was sold a lemon, but there is nothing I can do about it.

Filed Jun 20, 2023 · Transmission · VA

CVT transmission issues persist beyond the limited warranty extension that has now expired from Subaru. Vehicle RPMs regularly drop from 1000 to 500 when coming to a stop, causing engine to knock as it tries to stall. Vehicle then occasionally hesitates when attempting to move under power. Knocking and near stalling occasionally results in a sensation of vehicle being hit from behind while stopped with vehicle in drive and brakes applied.

Filed Jan 17, 2019 · Electrical, Engine · CO

Extended crank issue - I've had an extended crank issue with my car for the last 10 months. The car has been taken to the subaru dealership where it was purchased 3 time. The car spent 30 days in the shop due to this problem. The car is having a very hard time starting after it's been sitting for a few hours. And sometimes not starting at all, when it does eventually start it's cranking for an additional 10-30 seconds. One it does start the engine knocks and runs rough until it warm, then goes away. When the car was at the dealership, I was informed that the extended crank is a known issue for the year I have. I was told the computer system in the car needs to be replaced in order to fix the problem. I representative from subaru came out to the dealership to look at my car and 2 others same year make and model that were having the same problem. The representative deemed it "normal" he said " nothing I can do until a recall gets approved" and "subaru needs to fix bugs in the system". He also said that while the car has the extended crank issue it is putting more wear and tear on the engine and it would soon need to be replaced. I was then sent on my way because, they couldn't do anything for me. Needless to say the car is still having issues because of the extended crank, nothing has been resolved.

Filed Dec 15, 2015 · Brakes, Engine · 200 miles · WA

May 8th 2015 we purchased our 2015 subaru legacy 2.5i premium. #1. Very prominent coolant smell from passenger side engine area. Loosing coolant. #2. 600 miles- transmission/ ecu /throttle delay , a 3-5 sec delay in the response when going from (r) into (d) and the same 3-5 sec delay is duplicated when going from a stop to accelerating the car. Concerning. #3 3000 miles, loud wind noise is heard from all windows. Windows were replaced by dealer, but noise still exists. #4 the gas door will not release and continues to get stuck. #5 8,500 miles- excessive water entering into engine bay. While driving the engine bay gets completely soaked with water. Standing water in the battery tray, a river of water running down the inner fender walls inside the engine bay and water is entering into the fuse box. When engine gets wet it has a burning electrical smell. Water has also been found on the drivers side floorboard an in the spare tire area of trunk. #6 2,200 miles starting/motor concerns. The car will crank over, but doesn't start. The second attempt the car starts up and dies immediately. 3rd attempt car fires off an associated with bad gas smell/ rough running. The most recent time this happened to us (12/12/15), 1st attempt the car wouldn't start, 2nd time trying to start the car is fired up then died. 3rd attempt car started up running rough w/ a bad gas odor. It's associated w/ backfiring / popping sound through the exhaust. Recently has developed a low end sound/knock in motor between 1800 and 2200 rpms. #7 11,500 miles brake pedal goes to floor. Pedal isn't holding pressure. Vehicle pulls to the right an associated with a clunking sound coming from the right front wheel.

Filed Jan 13, 2015 · Engine · 68,390 miles · NY

Car has been owned for 2.5 years and has been driving well. There have not been any cel or other warning light problem indications. Car has had routine maintenance, recalls and last synthetic oil change was done at van bortel subaru, victor, ny on 11/28/14 (67,433 miles). On 12/23/14 in the evening, following a 7 hour highway trip, car abruptly developed a loud engine knock with vibrations and was choking for gas. On 12/24/14, car was brought into my local mechanic who determined there was a major internal engine failure and the car was inoperable. Vanbortel subaru service dept. Was contacted and gave me a quote for a rebuilt subaru short engine block for $6,600. With only a two year warranty. They also said the repair was not covered under warranty since it had 68,000 miles on it. No " goodwill assistance" from the dealership or soa was offered even though they have serviced 7 of my family's subarus over the past 10 years. And, the '09 legacy has a history of engine problems as documented in various online owner forums (eg. Nasioc) and by consumer reports who rated the '09 legacy as being "worse than average for major and minor engine problems" I had the short block engine swap performed by my independent mechanic and asked him to tear down the old engine. He reported that: "the # 1 connecting rod bearing completely failed and was grinding into the crankshaft. Resulting in engine failure." he further noted that the engine oil was full. I have expressed my concerns to vanbortel subaru and soa for the decline in their quality, integrity, customer services and increased potential for a serious accident, injury or being stranded on a highway without any prior symptoms or warnings.

Filed Jul 8, 2014 · Engine · 124,132 miles · OH

Two weeks before this incident, the vehicle's oil was changed. Then, on saturday, july 5, 2014, I was traveling on the I-465n onramp from I-70e in indianapolis and upon accelerating experienced engine power loss and a loud knocking sound when the engine rpms exceed 2,500. The vehicle was taken to dreyer & reinbold in greenwood where I learned the vehicle only had 0.7 quarts of oil in it and now needs the short block, gasket set, and oil pump replaced. Upon speaking with the technician, I learned that in my vehicle, including other subaru vehicles, the oil light does not illuminate until it's too late and virtually out of oil, thus causing catastrophic engine component failure. The technician stated that sometimes engine oil nuts or filters are not placed on vehicles and the dashboard's "engine oil" light fails to illuminate even after all the oil has been displaced. Updated 02/25/2015

Filed Nov 13, 2013 · Engine, Wheels · 55,000 miles · LA

Before this - engine replaced with very few miles - subaru claimed no warranty - insurance paid based on tiny leak in radiator - car just quit. Never knew of any leak - not water in garage floor ever. Then on 12/28/10 had heard loud knocking noise in front end. Subaru sent wrecker (2 hrs_ 1-way) to pick up car - replaced front end problems. Continued/constant problems with this vehicle - truly a lemon. I am 77 - have been stranded more than 2 x's recently - car just loses power - ck engine & cruise lights - also 10/9/12 dash lights on drove 6+ hours to service in new braunfels, tx. Nearest dealer is 2.5 hrs away 1-way. Need dealers no one else will even look at subaru. This is truly the subaru from hell!!!!! Limited income cannot buy another car but I should would if I could.

Filed Sep 24, 2012 · Engine · 115,000 miles · MT

Was driving on my road to go home and the dash board warning lights came on and heard a loud knocking sound. Pulled over immediately. Found out the engine blew a rod, cause is unknown.

Filed May 17, 2010 · Engine · 126,955 miles · CA

Car had been parked for 2 1/2 days. On cold start it made a horrible noise, check engine light came on and car died. I towed it to an auto repair shop. They said noise was internal motor noise. I authorized r&r of the oil pan and the found the #3 rod bearing spun. This vehicle has never been abused nor neglected and I have service records showing every service done on time. All oil changes were done every 3500 miles. Also.. At 92k miles my car developed a head gasket leak. Subaru has a warranty extension for 99-2002 subaru legacy headgaskets up to 8 years or 100,000 miles. Subaru declined coverage on my vehicle due to VIN # being outside of VIN # group they had extended.