Report: Chrysler repairing Pentastar V6 engines with revised cylinder head after reports of malfunction
AutomotiveNews reports that Chrysler dealers have been replacing cylinder heads on certain models equipped with the brand’s standard 3.6L Pentastar V6. According to the report, complaints have been recently filed with the National Highway Traffic Safety Administration regarding customers who’ve experienced excessive valve ticking, engine misfires, stalling, and loss of power. As a result, Chrysler has already redesigned a new head for the Pentastar V6.
But adding insult to injury, word is that Chrysler has also been experiencing a shortage of these replacement heads, leaving customers without their own vehicles for weeks while Chrysler picks up rental coverage.
Chrysler didn’t specifically comment to AutomotiveNews as to what the revised head features, other than it is “a more robust head.” New Pentastar V6s as of six weeks ago have been made with the revised cylinder head.
Roughly 1,300 vehicles have been held out of order due to the shortage of parts, according to a source closely associated with Chrysler’s parts database.
“The biggest mistake we made is taking our eye off the ball on service parts. That always gets the dealers’ attention,” said Doug Betts responding to these reports, Chrysler’s senior vice president for quality. “Our intention is to always satisfy the needs of the service market ahead of production. This came to my attention a couple weeks ago. We have parts in the pipeline to remedy that shortfall.”
When inquired about the problem with the Pentastar V6’s cylinder head, Chrysler’s executives declined to describe in detail as to the cause of the recent failures. Some have pondered the possibility of the Pentastar V6’s unique exhaust manifold, which channels all of the hot exhaust gasses through one outlet within the aluminum cylinder head. Most other modern engines have multiple outlets to channel hot exhaust gases to prevent significant heat build-up, which could lead to overheated and warped components.
Though in response, Bob Lee, Chrysler’s chief of engineering, said that excessive heat was not a cause of malfunction. Lee also claims that it is neither a manufacturer defect as only a small number of Pentastar 3.6L V6-equipped Chrysler vehicles have been reportedly affected. Instead, both Betts and Lee point the cause to ultra-rare circumstances such as varying fuel mixes and the way the car is driven as major contributing factors.
“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.”
Chrysler has been fixing all affected engines under warranty.
– By: Chris Chin