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Cayenne S 2007-2010 (957) High Pressure Fuel Pump (HPFP) Replacement DIY
My 2008 Cayenne S with 96,000 miles has been exhibiting fuel system issues. The problems started with long crank intervals and continued with loss of power, rough running, and eventually going into limp mode. Using my Durametric tool and the "actual values" menu I determined that the issues pointed to the HPFP. I compared the "fuel high pressure set point" and "fuel high pressure actual value" measurements and noticed that (1) at idle the car will require about 40 bar while the system was generating around 5.5 bar and that (2) the actual pressure value was unable to follow the set point value as throttle was applied. At full throttle the car will require about 120 bar, while my car was struggling to put out 20 to 30 bar. Also worth noting is that the low pressure fuel system (2 in-tank pumps) is supposed to supply a nominal pressure of about 5.5 bar. In other words, my high pressure system eventually failed completely and the car was simply running (poorly) on the low pressure system alone. Others here have had similar symptoms leading to the replacement of the HPFP. Following is a DIY replacement of the HPFP. I took the DIY route because Porsche will charge about 4 to 5 hours of labor for this job, which is actually reasonably simple for a DIYer. I sourced a remanufactured HPFP with an updated PN from Suncoast Porsche. There is a $90 core for the old pump and the total cost was around $850 after returning the core.
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Mihnea 2007 Cayman S Track Car 2004 911 GT3 2016 Cayenne S 2017 Macan S 2008 Cayenne S - Sold 2011 Boxster S - Sold 2007 Boxster S - Sold 2001 Boxster S - Sold |
#2
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Here are some step-by-step DIY instructions:
Remove the driver's side and rear engine bay cowling. Twist the plastic fasteners 90 degrees and they will pop out. Use a T25 torx to remove the two torx screws securing the rear cowling piece to the side pieces. Here is the engine bay with the cowling removed. The pump is located on the back of the driver's side engine head. There is a triangular metal shield behind the pump that needs to be removed first. It is number 16 in the diagram below. It's held in place by three 10mm bolts, number 17 in the diagram. The photo shows what you can actually see, looking at the engine. Indicated are some items that will make life easier if removed. Here is the shield, finally removed. I then removed one of the torx bolts for the engine hoist hook and zip tied it out of the way to give myself more room. Next, it's time to undo the high pressure fuel line going to the fuel rail. Now, remove the three bolts securing the pump to the block. Two of them are really long (labeled number 14 in the diagram above) and one is short (labeled number 13 in the diagram above). Leave number 15 alone as it does not go through the pump housing. All three are 10mm. Here is what the long ones look like. It's time to remove the pump. Jiggle it back until it comes out of the block. I don't have a picture of the electrical connector, but once the pump is free of the block, turn the pump until you can see the connector and undo it. You'll have to lift on a tab to free the connector. The low pressure fuel hose feeding the pump is flexible and can be removed after the pump is out. Here is the removed pump. And the low pressure line free. This is how all the parts are laid out. The three shield bolts screw into the top of the long pump bolts, which are threaded at the top. Prior to reassembly, it is important to determine whether the HPFP "clutch" has fallen off the end of the camshaft or not. The diagram below will help clarify the design. Number 5 in the diagram is the "clutch" while number 6 is a plastic stopper that is supposed to keep the clutch attached to the camshaft. In my case, the plastic stopper had fallen apart and allowed the clutch to fall off and down into one of the underbody linings. I failed to notice this during the disassembly process and proceeded to install the new pump without the clutch. Unfortunately, the camshaft will not drive the pump without the clutch, so I had to redo the entire procedure, but first I had to purchase a new stopper. Here is the stopper and clutch together, as they should be attached to the camshaft. FOR NEXT STEPS PLEASE GO TO PAGE 4, POST #40.
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Mihnea 2007 Cayman S Track Car 2004 911 GT3 2016 Cayenne S 2017 Macan S 2008 Cayenne S - Sold 2011 Boxster S - Sold 2007 Boxster S - Sold 2001 Boxster S - Sold Last edited by 987kmns; 01-30-2018 at 09:31 PM. Reason: Editing photos. |
#3
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Great writeup, as always.
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Collin M. I wear a cowboy hat. '86 951: lucky number 13...rare 6.0L edition. '06 M3: hers. |
#4
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Nice job! Thanks for sharing!
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Martin 2011 Cayman S (Gone) - Hardtop Blechster 2006 Cayman S (DD) 2016 Mazda CX-5 (Her DD) 2002 Boxster S (Gone) - Ragtop Blechster - Pura Patina! Dorkiphus: I buy it for the articles |
#5
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Nominated for HOF
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David D. '87 Targa - 2021 quickly disappearing... |
#6
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Excellent write-up, photos, and labeling!
HOF?-->Thanks, Jazz.
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Peter (not "Pete") K. 2016 Cayman S 1999 Miata ("SM") race car 2016 Toyota Highlander--tow vehicle/wife's DD 2017 VW GTI SE (DD) Gone and missed: 1992 Miata ("SSM") race car 2009 911 C2S Coupe 2004 Toyota Prius - sold to son's girlfriend 2006 Dodge Durango 2003 Acura MDX 86 Black 911 Coupe race car 86 Gold 911 Targa 82 WineRedMetallic 911 Targa Last edited by Dr K; 11-12-2014 at 02:15 PM. Reason: HOF granted! |
#7
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can you tell me what value you read to get the high pressure value. I have a 2009 base and dont see any values about the fuel pump pressure.
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#8
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Subscribed
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Vu It's not just the cars...It's the people! |
#9
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Thanks for the great writeup. Based on what I have been hearing it looks like this repair will not be uncommon.
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http://vimeo.com/29896988 “Those that can make you believe in absurdities can make you commit atrocities.” Voltaire. "There is grandeur in this view of life...." Darwin. The mountains are calling and I must go. “The earth has music for those who listen” Shakespeare. You Matter. (Until you multiply yourself times the speed of light squared. Then you Energy) “We’ve got lots of theories, we just don’t have the evidence’. |
#10
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I used my Durametric tool to connect to the DME and clicked on the "Actual Values" menu under the Engine Management tab. If you scroll through the list (there are lots and lots of different sensor readings) you will see both "Fuel high pressure set point" and "Fuel high pressure actual value". Check the selection box next to these values and they'll be displayed at the bottom of the screen. The setpoint is what the DME is requesting from the pump and the actual value is what is being delivered.
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Mihnea 2007 Cayman S Track Car 2004 911 GT3 2016 Cayenne S 2017 Macan S 2008 Cayenne S - Sold 2011 Boxster S - Sold 2007 Boxster S - Sold 2001 Boxster S - Sold |
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