As modern and well-designed as Chrysler's Pentastar V6 engine is, a fault in the cylinder heads has affected enough vehicle owners that Chrysler is voluntarily providing dealerships with replacement parts for the affected customers.
Automotive News’ Larry Vellequette has published a definitive article on Pentastar engine failures, which several other news sources have picked up on.
Chrysler has not elaborated on the specifics of the issue, but affected customers report a ticking sound from the engine, stalling, and other problems. The check-engine light illuminates on all affected engines. Chrysler's executives said the problem arises only with an unusual combination of factors, such as low-quality fuel and unspecified driving conditions. Chrysler said the issue does not disable the engine. The most telling admission is:
Betts, who as head of quality oversees a team of 1,200 people dedicated to improving Chrysler's once-woeful quality reputation, declined to identify the exact cause of the problem.
He said the malfunctions were the result of "an interaction of a lot of rare things that ultimately come together to affect a small percentage of the population." Those could include different fuel mixes and the way the vehicle is driven, he said, though he did not explain further.
Lee said there are limits to the percentage of Pentastars that will experience the malfunction because of the variables involved.
"You have to have this fuel characteristic, you have to have this drive cycle -- and all of these things have to line up in order to have this situation occur," Lee said. "That's why" the number of potentially affected engines "is so small. If it were a design defect, or if it affected [a basic component] like the integrated exhaust, we'd have issues on everything, which we don't."
A revised cylinder head design is already in production for new Pentastar engines, and Chrysler is supplying these new heads to dealer service departments under warranty for affected owners of Jeep Wrangler and Grand Cherokee, Dodge Avenger, Charger, Challenger, Caravan, and Journey, Chrysler 200, 300, and Town & Country vehicles.
Chrysler is without a doubt doing everything they can to fix this issue, as the Pentastar will be the company's only V6 engine once production of the archaic 3.7-liter V6 in the Ram 1500 and Jeep Liberty comes to an end this summer.