Hyundai Elantra knocking problems

Filed Oct 24, 2026 · Engine · UT

Vehicle Information: Year/Make/Model: 2017 Hyundai Elantra Value Edition Mileage: ~135,000 miles Engine: 2.0L Nu 4-Cylinder VIN: [XXX] Incidence Summary: Engine internal failure, metallic debris/shavings found in oil, severe knocking noise, high risk of sudden engine stall/failure while driving. Detailed Description of the Incident: While driving home, the vehicle began producing a loud, severe metallic knocking noise from the engine compartment. The engine continued running, but the noise persisted throughout the trip. Upon inspecting the vehicle, a certified mechanic removed the engine oil and discovered a significant amount of metallic debris and metal shavings inside the oil pan, indicating severe internal engine component wear (connecting rod bearing / crankshaft failure). The mechanic advised that the engine is at immediate risk of seizing or experiencing complete catastrophic failure. Safety Risk: A sudden engine failure or seizure while driving on a highway or at high speeds creates a critical safety hazard, as it can cause an immediate loss of power, loss of power steering/braking assistance, and significantly increase the risk of a crash or rear-end collision for me and surrounding traffic. Current Status: The vehicle is no longer safe to drive and has been grounded to prevent complete engine lockup or serious road accidents. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Oct 19, 2026 · Brakes · CA

My 2017 Hyundai Elantra SE 2.0L (outside Recall 157/17V063 VIN range) has suffered 7 intermittent brake failures since 06/03/2026 (~118,563 mi), involving total loss of braking power, a rock-hard pedal, and/or resistance during pedal depression. The vehicle is at Temecula Hyundai and available for inspection. SAFETY RISK: Across 7 incidents (06/03, 06/17, 06/23, 08/29, 09/19, 10/09, 10/11), the brake pedal either met strong resistance halfway down with rapid metallic ticking from the front-left/under-hood area and reduced stopping power, or became completely rock-hard with total loss of braking power for 5-10 seconds (frequently while braking downhill). On 09/19, 1-2 seconds of pedal resistance/ticking transitioned directly into a rock-hard pedal and total brake loss. On 06/03, I had to jump a curb to avoid traffic. On 06/23, 09/19, and 10/11, I had to use the emergency brake to stop. On 10/11, total brake loss approaching a stoplight forced a hard e-brake pull, locking the rear tires and spinning the car sideways in front of cross-traffic before brakes returned 8-10 seconds later. REPRODUCTION & INSPECTIONS: Inspected by Temecula Hyundai across 5 visits (96+ cumulative days in shop) and an independent shop (both verified brake pads, rotors, and calipers are good). In June 2026, a dealer technician reproduced the stiff brake pedal on a road test and replaced the brake booster under warranty (06/16), without documenting on the work order if vacuum check valve/hose or ABS HECU causes were ruled out as the root cause. Failures recurred within the same week. On 10/13, a dealer advisor confirmed a front-left growling/chirping noise on a road test, yet the dealer only suggested customer-pay brake pads (with "high confidence" it would fix the total/complete brake failures). WARNING LAMPS: Zero warning lights or codes have ever appeared before, during, or after any incident. A near-daily front-left growling and chirping noise is present (not constant during all braking).

Filed Oct 18, 2026 · Acceleration, Engine · MS

A month ago my car started making a knocking noise very loudly at start up, and once driving for about 5 to 8 minutes it kind of stops, my speed doesn't accelerate as normal and if I go over 67 mph feels like I'll lose control. I see Hyundai have a knock sensor recall and from the video on the website my car makes same sound but my 2023 Elantra isn't list on the recall list. I'm the first Original owner of the vehicle only at 80,000 miles

Filed Sep 29, 2026 · Engine · FL

Back in early July, I noticed a ticking sound coming from my engine so when I took it in to a Hyundai dealership, they told me the only way I could pursue any help further was by completing a oil consumption test, which I complied and paid for out-of-pocket very soon after within 48 hours my check engine light came on and was flashing. after pulling the code at an AutoZone which I have documentation of it was a P 1327 which signals that the car had entered limp mode. I very quickly reached out to Hyundai themselves and after going back-and-forth on paperwork, they assured me that since I had no coverage on the vehicle due to its mileageand that it was not produced in the same factory as the other recall vehicles with that same problem that they could not pay or help me with any of the services I would need done to my engine. They told me the only chance I had was by completing the oil consumption test, which would then put me and my safety at risk by driving a car with a faulty engine while it was also in limp mode. I’ve only had the car for about a year and a half when it threw the first sign at me and I’m now struggling to figure out how to afford a completely new engine all on my own with no financial assistance all because my car was not made in the same factory as all the other ones that have had the same issue. I have not been able to drive the vehicle in the last two months and it just put me into financial deficit, trying to figure out reliable transportation to get to my current employer. It also states that the previous owner must have had an engine inspection/replacement but was not specified of which specific action was taken on the official Hyundai website.

Filed Sep 26, 2026 · Engine · MS

I am reporting that there is not a recall but a factor warranty from the manufacture. Stating that the o ring in the 2019 hyundai elantra was not properly tempered. Which will cause the car to stall, rod bearing to break, and cause the car to set on fire. My report is that my 2019 hyundai elantra with 139,000 miles has did exactly that. O ring was bad and the rod bearing broke. When calling hyundai to report it they claim that my vehicle Vin number doesn't fall under that manufacture recall. Why doesn't it? This is exactly what happen to my car!!! Can anyone please help me. Thanks

Filed Sep 22, 2026 · Engine · FL

The vehicle experienced severe, sudden loss of power while driving, leaving the car unable to exceed approximately 40 MPH on public roads and highways. This restriction creates an immediate rear-end collision hazard and severely degrades acceleration under traffic conditions. Diagnostic & Technical History: The vehicle previously triggered Diagnostic Trouble Code (DTC) P1326 (Knock Sensor / Engine Limp Mode). Diagnostic testing at Holler Hyundai under Techline Case #2026040700281 confirmed severe internal mechanical compression failure in Cylinder 4. Cylinder 4 failed dry compression testing and required a wet compression test (oil added to the cylinder) to hold pressure at 151 PSI. Severe internal engine oil pass-through/blow-by from the damaged cylinder has clogged the catalytic converter with baked oil ash, creating extreme exhaust backpressure that physically restricts vehicle speed and throttle response. Holler Hyundai recently replaced the physical knock sensor to clear the active P1326 light, but the underlying internal mechanical engine damage and clogged exhaust remain unaddressed. Corporate & Warranty Refusal: Hyundai Motor America (Executive Corporate Case #43193886) has formally denied goodwill coverage and engine replacement. Corporate is refusing to address the internal mechanical failure without requiring out-of-pocket diagnostic procedures, despite documented cylinder failure and a severe ongoing highway safety hazard.

Filed Sep 10, 2026 · Engine · CA

The vehicle entered limp mode. The Hyundai dealer diagnosed a camshaft problem, said the repair would be covered, ordered the part, and began the work. After the engine was opened, the dealer noted sludge/varnish and denied coverage, claiming lack of maintenance. This VIN is included in safety recall 21V301 for improperly heat-treated piston oil rings on the 2.0L Nu MPI engine. Hyundai told the federal safety agency that chipped rings can scuff the cylinder bore, cause accelerated oil consumption, knocking, oil-pressure warning, connecting-rod bearing seizure, stall, and in limited cases fire. The published remedy is inspection of the cylinder bore and piston skirt, engine replacement if damage is found, and PNSS software, at no charge. Hyundai National Consumer Affairs Case #XXX. I sent a written demand that they complete Campaign 203 and not convert an open safety recall into a customer-pay job. On XXX, case manager Mohammad issued a letter denying only “limited warranty” coverage for lack of Owner’s Manual maintenance. That letter does not state whether the Campaign 203 bore/skirt inspection was done, does not state whether PNSS was installed, and does not decide the incomplete recall. Oil and filter were changed on a regular schedule by the owner’s family using the specified oil. A signed affidavit was provided. Hyundai’s warranty does not require dealer-only oil changes. The symptom of the recalled oil-consumption defect (varnish/sludge) is being used to refuse the recall remedy. The vehicle remains unrepaired. I have not authorized customer-pay work or disposal of parts. What I want the federal safety agency to do Record this as an incomplete recall remedy. Require Hyundai Motor America to complete Campaign 203 on VIN [XXX]: perform the official bore and piston-skirt inspection, replace the engine if abnormalities exist, install PNSS, and cover related camshaft/engine damage found when the engine was opened, at no charge. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Sep 4, 2026 · Engine · 120,286 miles · IL

The contact owns a 2019 Hyundai Elantra. The contact stated that while her husband was driving 35-40 MPH on a bridge, the engine made a loud banging and knocking sound, and the vehicle stalled. The driver shifted into neutral, coasted down the bridge with the engine off, and pulled over to the side of the road. The driver noticed an abnormal burning odor coming from the vehicle. The vehicle was towed to the residence, where the contact's husband performed an oil change and discovered a hole in the side of the engine block. The vehicle was then towed to a dealer, where it was confirmed that the failure was associated with the federal safety agency Campaign Number: 21V301000 (Engine); however, the repair was not covered because the VIN was not included in the recall. The failure mileage was approximately 120,286. The VIN was unavailable.

Filed Sep 3, 2026 · Engine · GA

2019 Hyundai Elantra with 2.0L Nu MPI engine suffered catastrophic engine failure at approximately 118,530 miles. Vehicle is currently at the [XXX] Hyundai dealership. Vehicle appears to fall within the exact parameters of Hyundai Recall 203/the federal safety agency 21V‑301. Have spoken to the dealership as well as Hyundai corporate and they have refused to either honor their own recall campaign or do a goodwill service to replace the engine, citing my VIN does not fall under their recall campaign, however they have yet to provide any reason, and according to their own campaign 203 recall information my vehicle meets the exact criteria. I am concerned the recall population may exclude vehicles suffering the same engine defect, and their clearly is a clerical error or something on their behalf, and they appear to not be interested in remedying it, which could and has in my case resulted in potential danger. My car died in the middle of [XXX], and had I been in heavy traffic and could not have coasted it down a hill to a parking lot almost certainly would have resulted in a collision. I was fortunate enough to at the time be in light traffic. Upon restarting car motor made a horrendous knocking noise, which is symptomatic of exactly what recall campaign 203 warned of with the defective engines they installed in my series of vehicles. Hyundai denied goodwill solely based on time in service and mileage rather than identifying a different failure mechanism, and as of the time of writing this has not provided an explanation of why according to them my VIN doesn't fall in their campaign, when clearly it should as it is the correct year, correct factory stock engine, correct place if manufacture, and the very same symptoms they published in their campaign. They have told me I need new engine, as was obvious by the fact it's disabled and sounds as if a rod has thrown. I have brought this to their attention every day for going on 2-3 weeks. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Aug 29, 2026 · Engine, Fuel system · NJ

Vehicle stalls while driving which is very dangerous. All dashboard lights go on prior to stalling. No engine light is on. Knocking sound coming from engine. Dealer states engine needs to be replaced. Car has been serviced regularly despite that Hyundai denies engine replacement. The knocking sound that engine does is common between this model and year but mysteriously there has not been engine recalls.