ricatic wrote:
My neighbor was a warranty audit engineer for VW for 5 years. He is very familiar with the official VW policy on CP4.xx warranty coverage. He has clearly stated several times to me when discussing the Bosch pump that VW was forced to take the position that all pumps are warranty...as I mentioned before...it was either that or a complete recall...He said VW was not happy but could not fight it further...
Evidently that Sauerkraut koolaid is not as strong as the Blue Stuff...
Regards
The big difference was that at TDIclub.com and their diesel owners, decided to get proactive and start a campaign to file every single failure of said HPFP's of any one that showed up on the club with one from a Google Search, and bombarded NHTSA with complaints and being proactive about it.
It further led to NHTSA opening up an Engineering Analysis case for the failed Bosch pumps. It also lead to discussions by a lot of engineers and laymen on TDIclub.com as to the cause of failure in the design. I know for a fact I was the only one on TDIclub to mention 3 or 4 pertinent observations on crank speed, pump speed in relationship to crank speed, roller rpm speed, a factor of the pump spinning 2x faster than the old VE pumps, a factor of Bosch going from 4 rollers at 2000 psi to one roller at 30,000 psi, and spinning at stupid rpms, and someone at NHTSA must have read my post on TDI club, because the wording in their questionaire to VW was looking awfully like "cut and paste" to me, when they grilled VW, Audi and Ford engineers with a complete questionaire, and all the points I made about design flaw were in there, and VW and Bosch had to answer.
It's fair to say a lot of questions asked by some of the smarter folks at TDI club that actually had failures, and pulled apart their pumps, like Ricatic did, ended up coming back to haunt VW and Bosch.
My take on it is this, based only on my laymen's observations... 1600 to 1800 bar pressure seems to be OK on these HPFP's with the solenoid injectors, and the HPFP's are rare then... However, change to 2000 psi and Piezo injectors, and the HPFP and system can't handle the additional load, sooner or later you'll get a failure.
I also think North American diesel fuel does not have enough lubricity in the D975 standard of 520 micron wear scar diesel fuel. Bosch tests and builds in Germany on fuel that's B7 and closer to 250 to 280 micron wear scar diesel fuel.
Moral of the story? Make sure, from day one on your diesel, that you run 1 to 2% biodiesel, minimum, for at least the first 2 to 3000 miles for good break in /run in on your diesel Bosch HPFP powered vehicle. Get that wear scar down to 250 to 280 micron from your diesel fuel.
It's also my belief that hammer heads in diesels, cowboys, and in general idiots that think that diesels are OK to run at full throttle, and especially the tuner boys, deserve what they get... this pump is indeed fragile, it will fail a lot sooner, rather than later, from the above type of gross abuse. This is a pump that needs to be babied. Roll your foot into the throttle, don't ever mash it, like you would on a gasser. Smooth driving makes them last a long long time, idiots with lead feet and twitchy big toes doing constant throttle input changes will pay dearly for their poor driving habits.
