2012 Jeep Wrangler engine problems

Related recalls

No recalls on file.

What owners say

1. Filed Jul 7, 2026TXEngine

   The engine's cylinder head/valve train has failed internally, allowing combustion gases to enter the cooling system — confirmed via a chemical block test performed by a master automotive technician on November 29, 2024, which verified combustion gases present in the coolant. This is a widely documented defect on this engine and model year, related to valve seat erosion in the cylinder head. Symptoms first appeared in June 2018 as an unusual higher-pitched, stressed sound…

   NHTSA complaint #11748922 · source
2. Filed Apr 1, 202671,756 miNYEngine

   The contact owns a 2012 Jeep Wrangler. The contact stated that while driving at 20 MPH, the check engine warning light illuminated. The local dealer was contacted, but the vehicle was not diagnosed or repaired. The vehicle was taken to an independent mechanic, where a scan was completed, and diagnostic trouble codes for the Emissions, engine misfire, timing chain, and crank position sensor failures were displayed. The manufacturer was not contacted. The failure mileage was…

   NHTSA complaint #11728445 · source
3. Filed Mar 26, 2026ILAirbagsElectrical SystemEngine

   My complaint is that I was sold a dangerously defective vehicle with a known, unrepaired “stop driving” airbag safety recall, was not warned about the deadly risk, and am now being told to move and tow the car in direct contradiction to official safety instructions. ### Factual background - The vehicle I purchased has a Takata‑type airbag safety recall that carries a formal “do not drive” or “stop driving” warning because the airbag can explode and kill or severely injure…

   NHTSA complaint #11727336 · source
4. Filed Oct 29, 2025CAEngine

   The vehicle exhibits a persistent valvetrain ticking noise associated with the rocker/lifter/cam components of the 3.6L Pentastar V6. The engine makes a rhythmic metallic tapping at idle and during acceleration. The noise has progressively worsened, leading to rough idle and occasional misfires. This issue is documented in multiple Stellantis technical service bulletins (e.g., TSB 09-015-24 and TSB 09-011-25) which attribute the noise to hydraulic lash adjuster and…

   NHTSA complaint #11696485 · source
5. Filed Sep 30, 2025MOEngine

   The vehicle exhibits a persistent valvetrain ticking noise associated with the rocker/lifter/cam components of the 3.6L Pentastar V6. The engine makes a rhythmic metallic tapping at idle and during acceleration. The noise has progressively worsened, leading to rough idle and occasional misfires. This issue is documented in multiple Stellantis technical service bulletins (e.g., TSB 09-015-24 and TSB 09-011-25) which attribute the noise to hydraulic lash adjuster and…

   NHTSA complaint #11690582 · source
6. Filed Jun 6, 2025ILEngine

   I am reporting a persistent and safety-relevant defect in my 2012 Jeep Wrangler with the 3.6L Pentastar engine. The vehicle is experiencing misfires on multiple cylinders, especially cylinders 1 and 5, triggering codes P0300, P0301, and P0305. These misfires result in loss of power, hesitation, and rough idle, creating serious safety concerns during acceleration or highway driving. Despite replacing spark plugs, ignition coils, the crankshaft position sensor, purge valve,…

   NHTSA complaint #11665284 · source
7. Filed Oct 15, 202455,000 miTXBrakesDriver Assistance & Safety TechEngine

   The contact owns a 2012 Jeep Wrangler. The contact stated that while operating the vehicle the ABS, Traction Control and check engine warning lights had remained illuminated. The contact indicated that while pressing the brake pedal to stop, the brake pedal extended to the floor causing the braking distance to become extended. The vehicle was taken to the local dealer who diagnosed that the ABS module was faulty and needed to be replaced. The vehicle was not yet repaired.…

   NHTSA complaint #11619915 · source
8. Filed Jan 4, 2024MDEngine

   In my 2012 Jeep I had to replace the engine and catalytic converters. The engine number 3 cylinder failed due to excessive ware causing lower compression. After the engine (long block) was replaced, one of the cylinders was miss firing. This miss firing was traced to micro cracks in the plastic/composite intake manifold (original and not part of the engine replacement). Because these micro cracks changed the fuel air ratio on specific cylinders by leaning out the cylinders…

   NHTSA complaint #11563525 · source
9. Filed Dec 28, 2023KYEngine

   Jeep Wrangler 3.6 liter 90k miles lifter making loud noise. Seems you had a recall about this on the 2012 and guess I missed out

   NHTSA complaint #11562348 · source
10. Filed Oct 11, 2023MOEngine

    6 days after an oil change, the temp gauge while driving went from cool to hot in under a mile and the engine temp light came on. There was coolant all over the underside of the car it was near catastrophic. I had to have it towed to the dealership for repairs. The faulty part was the oil filter adapter it was cracked by over tightening of the oil filter.

    NHTSA complaint #11549495 · source
11. Filed Apr 4, 2023VAEngineFuel, Hybrid & EV PropulsionTransmission & Drivetrain

    Engine Stalls Randomly while Driving. Will crank over several times and over approx 10-15 min. of cranking(Say every 3-5min) vehicle will and will restart. No check engine lights and no warning. The loss of power can be dangerous since brake and steering assist require engine to be running. Vehicle will be fine for several days local commute and problem will recur without warning, usually on longer commute. Vehicle is unsafe and unpredictable.

    NHTSA complaint #11515380 · source
12. Filed Dec 7, 2022UTEngine

    Cam sensor failed. Check engine light and traction control light appeared. Replaced and same problems occurred. May be wiring or cam/rocker issues.

    NHTSA complaint #11496427 · source

Source: U.S. National Highway Traffic Safety Administration (NHTSA) Office of Defects Investigation public data. Complaints are submitted by owners and are not verified by NHTSA or by us; a complaint does not prove a defect exists. View this vehicle on NHTSA.gov Methodology