I need some help figuring out a problem on my 2001 996 turbo tiptronic.

I have 2 confirmed failed fuel pumps and 1 (probably failed) still in the car not dissected yet. Please look at the picture and share with me your thoughts.
I have cut opened the previous failed 2 pumps and found the commutator (the part in contact with carbon brush) to have uneven wear. These 2 pumps each have only less than 5000 km on them.
Before this series of failed pumps, the previous one had more than 50000 km and was only changed out as preemptive maintainence. The tech who worked on the car had visually checked the in tank tubes for crack but found nothing. The electrical socket was burnt before, but fixed together with the first failed pump.

What could lead to such premature failure of the fuel pump? I rarely run the tank to below 1/4. The car runs perfectly smooth with an AP accessport tune. I have confirmed with the tuner no alternation was made to the fueling part.
(All 3 pumps are VDO.)
Please help and thank you.

 

Very odd, gotta be just **** luck this point as I can't fathom what would cause the actual motor to fail. And to add to that, I've had a few brand new OEM parts from Porsche be no good right out of the box.

 

My mind went straight to clogged filter. Surely you've already replaced it?? Pumps will overwork themselves trying to force fluid through a mean restriction

 

fuel filter replaced leas than 30000 km ago. I will again replace it this time. Any chance the check valves or pressure regulating valves along the supply line are bad? What to look at?

 

What about the wiring and connectors that feed the pump? These are known to go bad and heat up.

 

The connector on top of the hat looks normal, those underneath look ok too.

I am preparing to run an direct power supply from the battery, controlled by a relay which will be triggered by the stock positive line coming out from the ECU. Hope it helps to rectify any bad ground / wiring problem.

 

The fuel coming into the pump runs over the brushes to cool them. Is there any debris in the tank? You using a new filter sock? Bad ground could do that too or a bad relay, relay easy to check by opening it up and looking at the contacts. I would just drop a walbro 450 in there instead of the factory one anyway and add a second relay that feeds battery power direct.

 

I will use an AEM instead of a walbro 450. Walbro has too much flow for my stock engine. New filter sock came preinstalled with the pump, and it looked clean when removed with the dead pump. No visible debris in fuel tank neither.

 

I wonder if these are possibly counterfeit parts? Lots of this with Bosch, and it’s really hard to tell the difference.