2018 Jeep Grand Cherokee Engine Problems

The contact owned a 2018 Jeep Grand Cherokee. The contact stated that while unloading groceries out of her vehicle with the vehicle in park(P) and the engine on, grayish-white smoke began to emit from the vehicle without warning. The contact turned off the vehicle and checked under the hood, where she saw flames in the engine. The contact then ran to the fire department, which was nearby, and informed them of the fire. The fire department arrived at the scene with a fire truck and extinguished the fire. The police department also arrived at the scene, and a police report was filed. No injuries were reported due to the fire. The vehicle was destroyed as a result of the fire, but was not towed. The dealer or manufacturer had yet to be notified of the failure. The vehicle was not repaired. The failure mileage was approximately 74,000.

Check Engine light with Codes: PO300, and PO305. Misfire in Cylinder #5. Changed all spark plugs, and coils. Check engine still on, with same codes. Jeep dealer then said it was the cam shaft and needed new cam shaft head of a price tag of $8500. The car has been well maintained and has 75,200 miles on it. There is a known premature failure with the Pentastar Engine that is in this vehicle. Jeep is refusing to stand behind their product.

1. The issue involved the engine and emissions system, specifically a cylinder 3 misfire, accompanied by illumination of the check engine light and white smoke emitted from the exhaust. The vehicle was evaluated by an authorized Jeep dealership, which confirmed the cylinder misfire through diagnostic testing. At that time, per the diagnosis, coil 3 and all spark plugs were exchanged. This did not solve the issue. When picking up the car, check engine light was still illuminated and white smoke emitted from the exhaust. The affected components are in possession of the dealership, unsure if available upon request. 2. The engine misfire and associated white exhaust smoke created a risk of engine performance degradation, including potential loss of power, observed hesitation and stalling, which could impact the ability to safely operate the vehicle in traffic. Additionally, white smoke from the exhaust can impair visibility for surrounding drivers and may indicate an underlying engine condition that could worsen without warning, increasing the risk to the driver and others sharing the roadway. The chemical smell could also nauseate the person operating their vehicle, impeding their awareness and concentration. 3. This issue was proposed by an authorized Jeep dealership, then confirmed by two other mechanics. Dealer diagnostic records document the cylinder 3 misfire and investigation related to the check engine light and exhaust condition. 4. No inspection from manufacturer, police, or insurance representative. 5. Yes, the check engine light illuminated and the vehicle exhibited white smoke from the exhaust which prompted the service visit. Auto-start was not functioning as normal, with an error displayed on screen. Engine would sometimes stall upon start up during cold temperature days. NOTE: vehicle is currently with another mechanic awaiting an engine replacement, will upload that invoice once available.

Issue with camshaft. Dealership said there has been an influx of vehicles with the same engine and the same issues.

Warped cylinder head without engine overheating. Cylinder 4 misfire.

The check engine light keeps coming on. The Jeep repair shop says that it has to do with the flap on the gas tank where you put the gas in. Hence, the repair light keeps coming on so you never know if its real and needs to be addressed or if its the gas tank issue again

Water pump failure.

My 2018 Jeep Grand Cherokee suffered a sudden, catastrophic engine failure with no warning lights or alerts. Dealer confirmed the engine seized from overheating and cannot be repaired—replacement engines are on national backorder. This is my only vehicle, I’m 7 months pregnant, and I’ve been without transportation for 30+ days. This appears to be a widespread 3.6L Pentastar defect and a serious safety concern.

In September 2025, the vehicle was shaking upon idle when we started it. We did a test and learned it was somehow losing coolant. We took it to a mechanic who discovered it was burning coolant in the 5th cylinder. They diagnosed the issue as blown head gaskets caused by the engine being machined incorrectly by the manufacturer. This resulted in the need for a short block removal and replacement, resurfacing the cylinder heads, replacing the head gaskets, among with many smaller repairs. The cost was over $8,000 total for a manufacturing error. If left unresolved, this could have caused further mechanical issues and potentially a crash or other safety issues.

I purchased my Jeep in 2023 and have consistently stayed up to date on all required maintenance. I had no issues with the vehicle until recently, when the check engine light and the start/stop warning appeared out of nowhere. After inspection, the mechanic determined that the entire engine needs to be replaced due to severe coolant leakage. My vehicle has now been in the repair shop for over three months because the engine is on national backorder. I contacted the dealership, but they dismissed my concerns and told me that once the car is purchased, it’s no longer their responsibility. I then reached out to the manufacturer requesting a goodwill resolution, given the unreasonable repair delay and the national backorder of such a critical component. Lemon law mileage limits do not apply to goodwill assistance, trade-in support, or corporate escalations. Despite this, the manufacturer has refused to provide any explanation or documentation for why they cannot assist and it has been three months with no progress. There were no warnings or indicators that something was failing internally, and my mechanic confirmed there was absolutely nothing I could have done to prevent this. I’ve also seen numerous reports of this same issue affecting my specific make and model. Stellantis needs to take accountability. It is completely unfair that I am left without reliable transportation for months over an issue that was entirely out of my control.

TURBO supply line broke causing coolant to go all over the engine.

The contact owns a 2018 Jeep Grand Cherokee. The contact stated that while driving for approximately 10-minutes, there was an abnormal knocking sound coming from the vehicle while depressing the accelerator pedal. The RPM lowered and the vehicle failed to respond while depressing the accelerator pedal. There was no warning light illuminated. The failure persisted, and the contact coasted into a parking lot and there was an excessive amount of yellow-grayish smoke coming from the engine compartment. The contact exited the vehicle and became aware of an unknown liquid pouring onto the ground underneath the vehicle, with little pieces of debris and sparks igniting underneath the vehicle. While the contact was on the phone with 9-1-1 Emergency Services, there was a popping sound coming from the vehicle and underneath the hood and over the windshield became engulfed in flames. The Fire Department arrived at the scene and extinguished the fire. A fire report was filed. The contact sustained severe emotional distress because of the failure but had not sought medical attention. The vehicle was towed to an independent tow facility where the vehicle remained. Upon investigation, the contact linked the failure to NHTSA Campaign Number: 20V699000 (Engine and Engine Cooling). The contact stated that the Insurance Company had not yet determined if the vehicle was a total loss. The dealer and manufacturer were notified of the failure but offered no assistance. The failure mileage was approximately 104,000.

The contact owns a 2018 Jeep Grand Cherokee. The contact stated that while driving at an undisclosed speed, the check engine warning light started flashing on and off and the vehicle decelerated. The vehicle was taken to the local dealer who examined the engine and informed the contact that there were metal shavings inside the engine. The vehicle was not repaired. The local dealer was not contacted. The manufacturer was notified of the failure, but no assistance was offered. The failure mileage was 109,000.

The Head gaskets are leaking. Cost of parts to replace is $200 and cost of LABOR is over $4000 quoted from Cross Motors Jeep.

Head gasket/engine failure. Constant check engine light. First it was for a misfire and my engine was overheating. Had oil clogging the filter even though it was changed within the appropriate mileage. I got the check engine fixed April of 2024. May 20,2025, head gasket blew, causing me to now have to replace my engine completely. Same issues as previously reported

Since the beginning of this year, vehicle began to misfire. So far I have spent over $2000 in repairs including replacing spark plugs, ignition coils, fuel injectors and oil cooler and vehicle continues to misfire and blow white smoke from exhaust. I have been advised that it may be a head gasket issue, which could cost anywhere from $3000 to $5000 but could cost more in the event the engine needs to be completely replaced.

Rockers & cam shaft are worn and making ticking noise. I only have 86k on my 2018 Jeep Grand Cherokee, and am diligent with upkeep on the maintenance. This is a very known issue and should be recalled as I have not driven it anymore to prevent further damage to the engine, and also don't have the funds to fork out almost 5k.

The head gasket blows around 80,000 miles. This is a known problem consumers have with this vehicle. My estimate to have this fixed is over $6,000.00.

The vehicle experienced a failure of the engine lifters/rocker arms, which also caused failure of the intake camshaft. This resulted in severe misfires, loss of power, and left the vehicle completely inoperable. The failure created a hazardous situation when the vehicle lost acceleration and was unable to maintain safe driving speeds, placing my safety and the safety of others at risk of collision. The problem was confirmed by Lou’s Car Care and multiple Stellantis dealerships, including Maguire Chrysler Dodge Jeep Ram. All inspections identified failed rocker arms/lifters and the intake camshaft as the cause of the malfunction. Critically, Stellantis no longer produces replacement intake camshafts for this engine, and the part is listed as indefinitely back ordered and unavailable. This means there is no factory fix, leaving the vehicle permanently disabled. Prior to the failure, the only symptom was a faint ticking noise from the engine. No warning lights or dashboard messages appeared before the incident. The problem escalated suddenly without adequate warning, causing the vehicle to lose power unexpectedly. This failure has caused severe negative consequences for me and my family. Because the vehicle became inoperable and the repair could not be completed, I lost my job due to lack of reliable transportation. I also experienced financial hardship, including losing my vehicle to repossession. My family, including my newborn child, was left without dependable transportation, which created additional safety concerns in emergencies. The failed components remain available for inspection upon request. This issue is widespread across Stellantis vehicles yet has not been addressed through a recall, despite the fact that the defect can cause sudden stalling or total engine failure at unsafe speeds. The unavailability of replacement camshafts means affected vehicles cannot be repaired at all, leaving owners stranded and financially devastated.

As many others have reported, only 56K miles on this 3.6L Grand Cherokee. When I engage the passing gear an auto stop/start light comes on on the dash followed by the check engine light. Vehicle rides very rough (from a misfire). Taken to an independent shop; they changed plugs and coils but the problem persists. Also a knocking / ticking noise can be heard when accelerating.