NHTSA Complaint #11598602 — 2017 CHRYSLER PACIFICA

2017 Pacifica, front bank (also referred to as left side of 3.6 Pentastar engine) multiple cylinder misfire, due to failed head; 110,000 miles. Issues progressed exactly or very similarly as described by multiple (hundreds of owners) on Pacifica forums), most fail between 80,000 to 120,000 miles, with distribution between 50k and 150k. Suspect excessive heat in engine bay coupled with defective head manufacturing (Mexican built engines suspected to have higher failure rate) and faulty components leading to head failures (cracked heads, warped heads, faulty head gaskets) on 2017+ Pacificas. Rear head known to fail due to lack of sufficient cooling in position at back of engine bay. Vehicle also goes through one aux start/stop battery every 1-1.5 years (suspect early failures due to excessive heat, not overcharging issue that Chrysler recalled for). Vehicle also has history of faulty roller rockers and lifters, already had replaced once while in warranty period. Issue began as faulty cam phase sensor. When repairs made mechanic also noted that oil cooler was cracked. This is a faulty design remedied by Chrysler for 2022 models. Heat coupled with bad o-rings and/or overtightening of oil filter cap leads to crack in assembly allowing for oil and/or coolant loss. Chrysler has made no attempt to fix known issue on pre-2022 models. Repaired both at cost of $1033. Few days later P0300 code and loss of engine power. Diagnosed as faulty roller rockers, one of which had even broken off. Roller rockers, lifters, and cam replaced on left side of engine at cost of $2700. Mechanic pressure tested head and found no leakage. Drove home and multiple cylinder misfire occurred again with loss of power. Returned to mechanic. Suspect crack between intake and exhaust valve guides which opens as head heats (seems to occur once engine reaches 195 degrees F, which is just below normal operating range). Head replacement suggested but not recommended as I'll be upside down in vehicle.