2018 Jeep Wrangler Engine Problems

On March 19, 2026 I paid $5,778.87 for repairs to my 2018 Wrangler JL. Repairs included the replacement of warped cylinder head and failed head gasket with coolant getting into the combustion chamber, showing up as rough running, misfire, flashing check engine light, and burning coolant smell. On April 18, 2026, at approximately 10:30 pm, after attending the [XXX] concert at Bank of America stadium (+70,000 in attendance), the vehicle stalled and was unable to be restarted or moved to the shoulder of the highway. The vehicle failure occurred on I277 outside of Bank of America Stadium with hundreds of cars passing us as my wife and were stranded in the middle lane. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

I have a 2018 Jeep Wrangler JL Sport S (2 door) with approximately 66,000 miles. On March 26th, 2026 I had a flashing check engine light come up along with the vehicle shaking in low gears. I had the vehicle towed to the Jeep dealership (Gandrud Auto Group) from which I bought it from and upon their inspection they found the left bank head gasket leaking coolant into the combustion chamber causing misfires. This repair was over $5000 and took over a week to fix. The service ticket from Grandrud will be attached which lists all parts that needed to be replaced. This vehicle is much too new to be having these kinds of issues and Gandrud even stated that many customers with JL Wranglers have been coming to them with the same issue of the head gasket failing. 1. Left bank head gasket leaking coolant into the combustion chamber causing misfires. Photos will be attached. 2. Shaking vehicle. Had vehicle towed. 3. Dealership inspected and identified the issue. Invoice attached. 4. Check engine light came on for just one day back in December of 2025, was brought into Gandrud and it was a misfire code, no noticeable issues at the time however and check engine light went away. On March 26th, 2026 I had a flashing check engine light come up along with the vehicle shaking in low gears.

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. During diagnostic testing, multiple fault codes were identified, including P000A (camshaft position slow response), P0300 In addition to the diagnostic findings, I contacted and visited multiple automotive repair facilities regarding this issue. Each shop advised that they have previously serviced 2018 Jeep Wrangler JK models with the same 3.6L engine presenting identical symptoms and diagnostic codes, including timing correlation errors, misfires, and internal engine damage. Several repair facilities indicated that they have had the same make and model in their shops for the same failure, including vehicles with significantly lower mileage, with one reported case occurring at approximately 7,000 miles. Based on consistent feedback from multiple independent repair facilities, this condition appears to be a known and recurring mechanical issue associated with this vehicle model, rather than damage caused by misuse, neglect, or owner fault. (random/multiple cylinder misfires), P0017 and P0019 (camshaft/crankshaft timing correlation errors). Upon removal of the oil filter, metal debris was found in the oil filter cartridge, indicating possible internal engine damage. Based on these findings, the repair facility recommended engine replacement or major engine repair.

Started having misfire issues. Replaced spark plugs. problem continued. started having to add antifreeze regurlarly. 1 quart per 300 miles. multiple P0302 error codes. Dealer 1st tried to tell me was a loose coil pack. looked at it again and said needs a new head gasket possibly a whole new engine. 117,000 miles and this seems rediculous for a 60,000 dollar vehecle. Especially since Jeep already issued an extended 150,000 mile warranty for 2011-2013. with 100's of these same issues still happening on 2018's and latter they clearly did not correct the defect.

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 3.6 L Pentastar engine has been the subject of numerous owner complaints of ticking noise, power loss, misfire, and premature valvetrain failure. I understand there have been related Jeep Technical Service Bulletins (such as 09-002-14 and 09-008-18) addressing these types of failures. A class action lawsuit (Maugain et al. v. FCA US LLC) alleges defects in the 3.6L Pentastar engine’s valve train (rocker arms, lifters) and failure to disclose the defect. Maintenance History: Regular oil changes (every <6,000 miles) at approved service centers; no prior major engine internal repairs. Concern: The defect affects engine performance, may lead to catastrophic engine failure, and potentially reduces safe vehicle operation and control (power loss, hesitation). Relief Sought: I request the NHTSA open a vehicle safety defect investigation and compel FCA / Chrysler / Jeep to evaluate this condition under recall criteria.

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. How was your safety or the safety of others put at risk? FULL ENGINE AND THROTTLE FAILURE ON FREEWAY MULTIPLE TIMES, 1X ON A STRETCH OF FREEWAY WITH LITTLE TO NO SHOULDER WITH MY 1 YEAR OLD IN THE BACK SEAT. Has the problem been reproduced or confirmed by a dealer or independent service center? YES, FULL SERVICE REPAIR RECEIPTS ON HAND. Has the vehicle or component been inspected by the manufacturer, police, insurance representatives or others? YES Were there any warning lamps, messages or other symptoms of the problem prior to the failure, and when did they first appear? NO

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. Forums online suggest similar issues with other 2018 - 2023 jeep / chrysler engines.

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. Dealership replaced radiator, head gasket repair, etc. since just February. Car was towed to dealership. 2 holes in engine at the bottom. Dealership claims they don't know why. After researching this particular engine and car, I feel that vehicle has a lot of issues. I don't feel that it is safe. I think a safety recall should be considered.

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 vehicle was taken to an authorized dealership, where a hydrocarbon test was performed and failed — confirming a likely head gasket failure on the driver-side cylinder head. The technician suspected a defect in the cooling system. I was quoted $4,500 just for engine disassembly, before any repairs. The vehicle is now undrivable and is being sent to another independent shop for a second opinion, costing an additional $250. My Wrangler has been properly maintained, and there is no evidence of abuse or neglect. I have attached a dealership invoice and diagnostic notes. This kind of failure should not occur on a well-maintained vehicle with only 40,000 miles. After researching the issue, I discovered that other Jeep owners have reported similar overheating and head gasket failures, particularly in models equipped with the 3.6L Pentastar engine. Technical Service Bulletin (TSB) 18-078-18 Rev A describes cooling system concerns that may contribute to this type of failure. I believe this may indicate a broader defect in the engine or cooling system. Stellantis has not responded to my repeated requests for assistance. I am filing this report to document the issue and request a formal investigation, as this may be part of a wider pattern of early engine failure affecting this vehicle model. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

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. To further complicate things, it took the dealership over a month to get a replacement camshaft in and installed, due to an abnormally high demand for replacement camshafts; this suggests a systemic problem with the engine, especially considering the problematic history of earlier versions of the 3.6L Pentastar V6 (1). https://static.nhtsa.gov/odi/tsbs/2014/MC-10069161-0335.pdf

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. This issue should be brought up to US consumer protection and be covered by the manufacturer. My 2018 Jeep has 71,000 miles! The Engine should not have a catastrophic failure this early in its life.

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 dealer advised the oil cooler was manufactured as a plastic component and repeatedly would fail causing the oi to leak out of the engine. the engine oil cooler was replaced with a newly designed metal part. the oil cooler failure also caused the oil pressure sensor to fail. repairs totaled $1942.07 for jeep's faulty designed. repairs were made by the jeep dealer. repairs were paid out of pocket and not covered by warranty. the jeep had just hit 100,442 miles when the failure occurred. jeep online forums have repeatedly posted about this problem. jeep needs to recall the faulty design that can cause the engine to leak out all the oil without warning. safety of us and others is at risk because the oil leaks out without warning, other then the check engine light coming on. no low oil or low oil pressure light ever illuminated. same can result in drivers being stranded on the road or result in engine failure.

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.

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. The contact stated that the failure had occurred while driving on a busy highway full of traffic and tractor-trailers. The contact stated that the vehicle was stuck in an unsafe location, in the middle of the highway. The contact exited the vehicle, trying to get to a safe area, onto the shoulder of the road. The contact stated that the grounds were icy and snowy. The contact stated that while crossing the highway on foot, trying to get to the shoulder of the road, the contact fell. The contact was transported to the local Medical Center by ambulance. The contact sustained a fractured left leg and fractured left knee. The contact stated that medical treatment was ongoing. The vehicle was towed to the dealer, where the vehicle was diagnosed with engine failure. The contact was informed that the engine needed to be replaced. The vehicle was not repaired. In addition, the contact stated that the failure occurred a month after the vehicle was purchased. The manufacturer was not made aware of the failure. The failure mileage was approximately 61,000. The VIN was unavailable.

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. During my last oil change my mechanic informed me he has seen this issue and multiple times on other Jeep wranglers. The vehicle is available for inspection The vehicle has not been inspected by of the listed parties No warning lamps the symptoms are the car making a humming noise after driving about an miles, leaking antifreeze as soon as I add it to the compartment. I’m constantly refilling it with antifreeze due to this, and vehicle overheating.

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 vehicle overheats, starts rough, idles rough, loses power, mpg tanks and its a huge safety issue (I drive my 2 year old son around a lot, as well as my dog).

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 vehicle was towed to an independent dealer where it was diagnosed that camshaft phasers had failed, and metal shavings were discovered inside the engine. The vehicle was not repaired. The local dealer was contacted, but the vehicle was not diagnosed or repaired. The manufacturer was notified of the failure and referred the contact to the NHTSA Hotline for assistance. The failure mileage was approximately 81,000.

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.

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. In addition, the vehicle failed to accelerate while driving uphill or downhill. The vehicle was taken to the dealer, where the catalytic converter was replaced. After several more tests on the vehicle, it was determined that there was a leak in the engine block, and that the engine needed to be replaced. The vehicle was not repaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 98,000.

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. I took it to get a second opinion and this shop just completed the same repair on my exact vehicle. It wasn't the head gasket. He said the cylinder is cracked and it would need to be completely replaced. $10k. That it is a factor defect and that Chrysler has been aware of the issue but is currently not doing anything about issue. He said they extensively searched the cylinder head and could not see where the crack was but Chrysler's recommendation was just replace the cylinder because that is where the issue is. I cannot afford to spend $10k on a repair. The vehicle is not even that old to have this issue, it is a 2018. Chrysler told my mechanic that it was a factor defect, a malfunction in the actual part, but that a recall hasn't been issued yet.