2021 Mercedes-Benz GLA 250 4MATIC Owner Complaints

On 7/17/26, while driving at highway speed, the check engine light illuminated and the vehicle lost power and shut off. I safely pulled over. It would not restart; a red battery warning displayed. Towed to Mercedes-Benz of Wilkes-Barre, RO #8388432. Dealer found battery severely discharged, replaced it, then found engine would not turn by hand. Diagnosis: internal engine damage/seized; recommended full engine replacement, est. $20,128, on a 2021 GLA 250 with 82,137 miles. MBUSA TSB MC-10241534-0001 (8/4/2023) extends the emission warranty on the exhaust valve assembly (cylinder head, exhaust valves, valve seat rings/guides) on the M260 2.0L turbo engine from 4yr/50k mi to 15yr/150k mi, covering MY2021-2022 GLA 250. My vehicle falls within this window. The bulletin's defect (valve guide/seat wear causing misfire and MIL activation) is consistent with the check engine light observed at failure. I have repeatedly asked MBUSA in writing to confirm whether the DTCs referenced in this bulletin were pulled/reviewed, and whether my case was cross-checked against the bulletin before any offer. MBUSA has not provided a written response. Reps made verbal offers ($2,100 toward the engine; separately $800.20 "service credit" equal to a battery charge that does not appear to have been performed), and on one call described the bulletin as "only a sensor issue," inconsistent with its own text. Filing to document a possible unaddressed engine defect on a GLA 250 within this TSB's covered model years, and concern that vehicles with catastrophic seizure may not be evaluated against this known condition before being treated as ordinary out-of-warranty repairs.

NHTSA ID

11765458

Incident

Jul 17, 2026

I recently purchased my vehicle with under 30k miles in July of 2026. Not long after my purchase my car began roughly idling with a blinking check engine light, and soon after the engine began misfiring. This also cause loss of power when attempting to accelerate creating dangerous conditions in high traffic/fast paced areas. After lots of research I found several reports of owners with cylinder failures. The dealership only responded to fixing the issue after calling them out directly on the issue.

NHTSA ID

11729834

Incident

Apr 6, 2026

Component/System: Engine cooling and lubrication system. Coolant was found mixing with engine oil (milky oil), indicating internal engine failure (I was informed it could be oil cooler/housing, thermostat, head gasket, or related components). Vehicle is currently at an authorized Mercedes-Benz dealership and available for inspection. The front left inner lining of my front break pad also "failed" inspection and the other 3 front break pads say "caution" and I never received a notification or warning about my breaks. Safety Risk: Coolant contamination of engine oil can cause sudden engine failure or loss of power without warning, creating a serious safety risk while driving, especially at highway speeds. There was no indication that engine oil was mixing with coolant, check engine light failed to illuminate/ no diagnostic warning illuminated. The condition was discovered incidentally during routine maintenance, which prevented any opportunity for corrective action prior to the failure. Confirmation: The condition was confirmed by an authorized Mercedes-Benz dealership during routine maintenance. The dealership stated the failure was not caused by owner misuse.Inspection: Vehicle has been inspected by an authorized Mercedes-Benz dealership (manufacturer representative). No police or insurance inspection occurred, as there was no accident or external event. Warnings/Symptoms: No check engine light or diagnostic warning ever illuminated. The issue was discovered incidentally after I received a low battery voltage notification and a routine maintenance reminder indicating service was due in approximately 1,000 miles, which I arranged promptly. The manufacturer will not perform full diagnostic teardown to determine the root cause unless I pay approximately $3,000 out of pocket. Link to video: [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11715960

Incident

Jan 27, 2026