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Message: [QUOTE="BBottoms, post: 936032, member: 1421"] VW Common Rail TDI's use the Bosch CP4.1 HPFP and they have been having similar pump failure issues. However, VW seems to be footing the bill regularly instead of denying warranties like Ford. Just like the 6.7, when the CP4.1 grenades it takes out the entire low pressure and high pressure system including injectors with ~$7k repair bills. VW somewhat attributes the failures to people putting gas in the tank and even have a 'recall' on the common rail TDI's to retrofit to fuel filler to help prevent misfueling. However, there are several on the forums that seem very meticulous and knowledgeable and not the sort to fill up with gas and they still have issues. The TDI's have a single filter fuel system with no water separator so I'm sure water in fuel is a contributing factor to some of these failures. One of the TDI vendors, 2microntech, has actually come up with a set up that is supposed to prevent a grenaded HPFP from taking out everything else. First, it runs a filter in-line on the HPFP return to catch any trash before it goes back to the tank and contaminates the rest of the low pressure system. There's also a 2nd piece that actually reroutes flow at the metering valve by separating the low pressure and high pressure sides of the HPFP so that a failure of the cam doesn't send debris into the rails and injectors. After looking at this system for my wife's 2010 Jetta I got to thinking why something similar couldn't be made for common rail trucks. It's an insurance cost up front that you may never need, but if you do grenade a HPFP it should limit the damage to a new pump and a few feet of fuel lines instead of an entire fuel system or motor. This is the VW system. There's a nifty diagram on the "Pure Flow Adaptor" page that shows a cross section of a CP4.1 HPFP and how it separates the flow. Not sure how similar a CP4.2 or K16 pump is and if something similar could be done for the trucks? [url]http://2microntech.com/[/url] [/QUOTE]