2018 Jeep Wrangler Engine Problems

On January 14, 2026, my 2018 Jeep Wrangler JK Sport (3.6L) with approximately 134,099 miles was inspected at Cox’s Automotive & Repair Inc. due to a check engine light and rough engine operation.

Started having misfire issues. Replaced spark plugs. problem continued.

The Check Engine light illuminated and diagnostic code P219A was recorded (Bank 1 Air/Fuel Ratio Imbalance), and the engine has a ticking noise. The dealership has indicated the issue likely involves the valvetrain/rocker arms/lifters and will require engine internal repair (valve cover removal, spark plug replacement, possible rocker arm replacement) estimated at ~$2,900-$4,500.

the vehicle was taken to the dealer because the check engine light was on. we were told the oil cooler was leaking and there was no oil in the vehicle. at no time did the low oil indicator come on.

The 3.6l v6 (mostly in the 2014-2020 wrangler) has a known issue for cylinder 4, 5 and 6 misfires, warping, metal shavings, damaged cams, ticking, overheating etc. My wrangler has had this issue multiple times and the cost to repair it is well over $4000 each time. The first time, my wrangler had 85000 miles and now it has 135,000 miles.

The contact owns a 2018 Jeep Wrangler. The contact stated after parking and turning off the vehicle, she saw smoke exiting from the hood. The contact stated she removed her two infants from the vehicle before locating the fire extinguisher she had available in the vehicle. The contact stated the fire extinguisher was broken but was able to extinguish the fire with a fire extinguisher that was provided by a school bus driver that was in the area. The fire department did arrive at the location after the fire was extinguished and filed a fire report. The contact was not aware if the police deputy at the scene filed a police report. The contact stated she burned her right middle finder while extinguishing the fire but did not seek medical attention for her injury. The vehicle was not drivable. The contact towed to the local dealer and made them aware of the failure. The vehicle was not diagnosed or repaired. The manufacturer had been informed of the failure. The failure mileage was approximately 40,800.

I was on a major highway when the Jeep wouldn't go above 10 miles per hour and almost causing me to get rear ended. I had it at the dealer at least 4 times, they can't find the problem. They replaced ABS controller, still they can't find the problem.

When the in motion the motor has a strong noise like the piston where broken, I have take to services dealer and they said it normal, then second time the had to clean the piston that I paid for $390.00. The noise continued you feel like the motor is going to exploded. I will take it back for the fourth time.

The contact owns a 2018 Jeep Wrangler. The contact stated that while driving at an undisclosed speed, the vehicle stalled, and the engine seized. In addition, the contact stated that several unknown warning lights were illuminated.

My Jeep began misfiring, giving a P0304 error code via the ODB. On June 2nd 2025, we took it to the Sandy Sansing CDJR Dealership. They determined that my 3.6L Pentastar V6 engine needed a new camshaft and lifters, despite having only 42,609 miles on it.

The engine blew while I was driving on the highway without warning. Several repairs since January and have had the car at just 2 years. Maintenance has been kept.

The contact owns a 2018 Jeep Wrangler. The contact stated that while his daughter was driving at an undisclosed speed, the vehicle stalled. No warning light was illuminated.

The contact owns a 2018 Jeep Wrangler. The contact stated while his son was driving approximately 30 MPH and slowing down for a traffic signal, the vehicle lunged forward, stalled, and then came to an abrupt stop. The contact stated that several unknown warning lights were illuminated and the windshield wipers engaged independently.

Constant stalling a any speeds dealers cannot fix problem

What component or system failed or malfunctioned, and is it available for inspection upon request? THE THROTTLE FAILED ON THE FREEWAY DUE TO A BREAK IN THE ENGINE HARNESS. HAVE FULL REPAIR RECEIPTS FROM SHOP.

The contact owns a 2018 Jeep Wrangler. The contact stated that while driving at an undisclosed speed, the vehicle hesitated and failed to accelerate as intended while depressing the accelerator pedal. The check engine warning light was illuminated.

Vehicle: 2018 Jeep Wrangler Sport Unlimited VIN: [XXX] Mileage at failure: 40,631 miles Issue Date: [XXX] Component: Engine / Cooling System / Head Gasket My 2018 Jeep Wrangler began experiencing overheating issues at approximately 40,000 miles. The engine cooling fan was frequently running on high, and I noticed an increase in coolant loss.

The 3.6L Pentastar engine has a know engine problem with the Cam, valves, lifters. I am a lucky enough to have the same ticking issues as millions of other unsuspecting customers. They was just quoted $6,000 dollars for the repair at our local Dodge dealer for a know defect on this particular engine.

My vehicle’s cooling system continues to develop leaks in the antifreeze line/reservoir. I’ve had it repaired three times, but the problem returns each time, causing the engine to lose coolant and overheat. The coolant reservoir continuously cracks little by little my vehicle has broken down twice due to overheating.

The oil filter housing/oil cooler is made of plastic and every Jeep Wrangler ends up leaking because of it and it should be a recall.

I have put thousands of dollars already into the motor because my Jeep continually overheats and looses coolant. Its been in the shop countless times over the last year with the same issue. I was told it was the head gasket with is a $3k job.

Clutch - The Sansone Dealer located in Avenel, NJ has informed me that they did not have the part at the time and that I would receive a call. I never got a call so I decided to take the car back to them and now I'm being told they would need to hold onto the car for at least 48-hrs to diagnose the car. I don't understand why when they should be aware of the recall.

Head gasket failed due to a manufacturing flaw in the engine block. Coolant leaked internally from the cooling passage into cylinder one causing a hydro lock. No external leaks.

The oil housing unit has cracked and has to be replaced. The Jeep is currently in the shop and they discovered that it is made of plastic and cracked. I had oil pouring out when I took it to the shop. After doing some research, apparently this is a problem with Jeeps.

OIl Cooler failure resulting in oil spill onto the transmission and motor housing. Per discussions of JK forums and other associated websites, this is a common issue with the 3.6 penstar motors. It was recalled on the Jeep Cherokees; however, failure to recall on the JK models were not available.

The contact owns a 2008 Jeep Wrangler. The contact stated that while driving at an undisclosed speed, the steering wheel seized. The stability control, traction control, and ABS warning lights were illuminated, and the Service Shifter message was displayed.

Coolant reservoir cracked to allow coolant to leak at 5800 miles.

Began smelling coolant (sweet smell), although could not find leak. At 15,600 miles (may 2020), vehicle was brought to jeep dlr for service. Found small cracks in the plastic portion of the radiator.

Radiator leak (failure). Jeep dealer confirmed and repair is in process.

Tl* the contact owns a 2018 jeep wrangler. While parking, the vehicle made a revving sound before the contact pressed the ignition button to turn off the vehicle. The engine some how reeved up and accelerated and jumped the curve and hit a building.

VEHICLE SEEMS TO REV UP ON ITS OWN/GAS PEDAL FEELS LIKE IT STICKS

When I first turn on the heater on cold morning, a maple syrup smell like antifreeze comes out of the dash vents. My coolant overflow tank looses about 1/4" coolant in 2000 miles. I believe there is a pin hole leak in the heater core.

I have a 2018 sahara with approx 1500 miles on it. Since day one I have felt like its idled rough a constant heavy vibration in the engine so much so that you can physically see the plastic windows of the soft top moving and the front tires and the seats shaking.

Left headgasket blew at 51k miles / Sept 2024. Second headgasket (waiting on confirmation of left or right) blew at 62k miles. Vehicle is well maintained.

Start and Stop button light came off and vehicle stopped drive. I’m the last 2 years I have to replace battery 3 times.

Told I need a new engine, never over did anything. An, used only as a daily driver. No extreme use.

The frame bracket for the engine mount has a vertical slot instead of the traditional round hole. This allows the engine to climb out of the mount in case the cross bolt gets loosened even slightly. I discovered this flaw when my engine started twisting and the output yoke on the rear driveshaft was rubbing against the fuel tank.

While braking the jeep, the braking system didn't override the engine. Jeep kept going in drive instead of stopping. I had to put it in neutral to get the jeep stopped.