I have a 2014 Jeep Grand Cherokee Summit with the 3.0L EcoDiesel and I've been struggling to resolve an overheating issue for the past few months. It's virtually undriveable and you have to drive it extremely gentle as to not make it overheat. I am mechanically inclined and do all of my own maintenance, and this has all begun when a dealership released the vehicle back to me with the expansion tank cap removed, which immediately overheated 10 minutes after picking up the vehicle. I've had nothing but problems since then.
The issue can be repeatedly duplicated and the engine will begin to overheat if there's any sort of load (climbing a decent grade on the freeway or surface streets, WOT, etc). If you back off and slow down, the temperatures will decrease and you can prevent it from overheating. Running at 75 mph on a flat freeway, the oil temps are steadily around 221 degrees and the coolant gauge needle is a bit elevated. To compare, the oil used to run around 205 degrees while cruising on the freeway. If you continue to push it just a little (even WOT while going downhill), the coolant temperature increases, oil temperature increases to over 232 degrees and then it will reach the "point of no return" and immediately overheat (coolant will increase its temperature to maximum, oil temperatures will increase to 270+ degrees if you attempt further driving, etc).
When driving it (and not overheating), I can turn on the heater and it will blow extremely hot air. When it's fully overheating (coolant temperature gauge is maxed out, and about 235 F according to AlfaOBD), I can turn on the heater inside the vehicle and there is NO HEAT! Additionally, the air coming off of the radiator at this time feels extremely cool, as if the radiator isn't even hot.
I have replaced the thermostat, and have duplicated the issue with the thermostat removed from the housing. After this, I discovered that the water pump was leaking, so I have also replaced the water pump with a brand new OEM Mopar water pump and all accompanying seals/o-rings. Concerned that there was a blockage in the radiator or heater core, I reverse flushed the radiator, heater core and engine, and then drove around for a few days with a chemical cleaner. After this, I reverse flushed everything again, used a professional strong chemical cleaner, reverse flushed again and then refilled with Mopar 68163848AB coolant mixed down to 50/50. Vacuum fill tool confirms that there are no leaks present in the cooling system. The EGR cooler was replaced under its recall warranty about 3,000 miles ago. Wondering if it was a warped head due to past overheating, I attempted to check for combustion leaks using the UView Combustion Leak Tester, but there are no combustion gasses present in the expansion tank.
Does anyone have any ideas why this could be happening? Thanks so much for any insight!
The issue can be repeatedly duplicated and the engine will begin to overheat if there's any sort of load (climbing a decent grade on the freeway or surface streets, WOT, etc). If you back off and slow down, the temperatures will decrease and you can prevent it from overheating. Running at 75 mph on a flat freeway, the oil temps are steadily around 221 degrees and the coolant gauge needle is a bit elevated. To compare, the oil used to run around 205 degrees while cruising on the freeway. If you continue to push it just a little (even WOT while going downhill), the coolant temperature increases, oil temperature increases to over 232 degrees and then it will reach the "point of no return" and immediately overheat (coolant will increase its temperature to maximum, oil temperatures will increase to 270+ degrees if you attempt further driving, etc).
When driving it (and not overheating), I can turn on the heater and it will blow extremely hot air. When it's fully overheating (coolant temperature gauge is maxed out, and about 235 F according to AlfaOBD), I can turn on the heater inside the vehicle and there is NO HEAT! Additionally, the air coming off of the radiator at this time feels extremely cool, as if the radiator isn't even hot.
I have replaced the thermostat, and have duplicated the issue with the thermostat removed from the housing. After this, I discovered that the water pump was leaking, so I have also replaced the water pump with a brand new OEM Mopar water pump and all accompanying seals/o-rings. Concerned that there was a blockage in the radiator or heater core, I reverse flushed the radiator, heater core and engine, and then drove around for a few days with a chemical cleaner. After this, I reverse flushed everything again, used a professional strong chemical cleaner, reverse flushed again and then refilled with Mopar 68163848AB coolant mixed down to 50/50. Vacuum fill tool confirms that there are no leaks present in the cooling system. The EGR cooler was replaced under its recall warranty about 3,000 miles ago. Wondering if it was a warped head due to past overheating, I attempted to check for combustion leaks using the UView Combustion Leak Tester, but there are no combustion gasses present in the expansion tank.
Does anyone have any ideas why this could be happening? Thanks so much for any insight!