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I'd say no, but I've had only about 3 years' experience with direct-injected fuel systems using mechanically driven HPFPs. The first was the car prior to this Macan, a 2009 Carrera C2 that I owned for 2 1/2 years and 10,000 miles. That was first year of the new 9A1 engine Porsche fitted in the 911; I had no problems at all. I do know BMW had a lot of issues with these pumps when they introduced the N54 engine. Pierburg is OEM on these pumps for many German cars.
 

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You're talking about the high pressure fuel pumps (there's one on each bank) that are mechanically driven by the intake camshafts. Take off the engine cover and you'll see them. They're expensive - $554 on FCP Euro, $361 on Rock Auto. Replacement doesn't look too difficult but the catch is you're dealing with extremely high fuel pressure when engine is running. A fuel leak on top of the engine caused by incorrect replacement would be bad news.

Because these pumps are mechanically driven what I recommend is more frequent oil changes than Porsche's 1 year/10,000 mile interval. Cut that in half and use A40-qualified oil. Your engine will appreciate it. These pumps are controlled electronically though, and from what I've read that's the more common failure point.

If a HPFP fails (I think dual failure is unlikely unless fuel rails are clogged with debris) the engine goes into limp mode with accompanying dashboard notice. The in-tank electric fuel pump is capable of supplying fuel for reduced power.
Thank You, I will start changing the engine oil every 5,000 mile interval. I do it myself so the cost is minimal $75.
 

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I've got a noisy left bank HPFP and plan on changing it out myself since we're two years out of warranty. Came up empty looking for a Schrader valve. Anyone know the location of same or how to bleed off pressure?
 

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I don’t know the correct Porsche procedure but if I was replacing I would either locate fuel pump fuse or relay and remove. Then start motor, it will stop when it has no fuel pressures remaining, or very little pressure.
Or wrap a rag around fitting to be loosened to catch fuel, there won’t be much volume of fuel released. Use compressed air to disperse fuel / fumes.
 

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I've not done it on a Porsche, but on the last vehicle I did with an HPFP, you just pull the fuse/relay and wait until it dies.

Wear a face shield AND glasses AND cover with a rag when you pull those lines though, they often still squirt. Have a fire extinguisher (preferably CO2) handy and do it only on a cold vehicle (no hot exhaust).
 

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I assume with the "pull the fuse/relay, then start 'til it dies" method, it will throw a code or two, right?
 

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SomeGuy, I would refrain from using a CO2 on any vehicle fire unless that was all I had available. Cleanup would be difficult at best. I have 5 and 10 lb. HALON's strategically placed around my garage and 2.5 HALON's in all our vehicles. Also have a few of the new ELEMENT 50 fire extinguishers as well.
 

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You can trigger an injector using a 9v battery. So when the engine is cold, locate an easy injector terminal and light 'er up.
 

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Won't that flood a cylinder with a whole lot of gas?
 

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I don't think so. There is no pressure reservoir in the system so the pressure should bleed off quickly. If it takes a while you can always remove the spark plug and vacuum the gas out.
 

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I just checked my Owner's Vehicle Emissions Warranty booklet and it appears that the HPFP is one of the components covered for 7 years or 70,000 miles. Calling my dealer tomorrow. Will report back.
 
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SomeGuy, I would refrain from using a CO2 on any vehicle fire unless that was all I had available. Cleanup would be difficult at best. I have 5 and 10 lb. HALON's strategically placed around my garage and 2.5 HALON's in all our vehicles. Also have a few of the new ELEMENT 50 fire extinguishers as well.
CO2 evaporates and is rated for BC which is fuel and electrical. You're thinking ABC dry chemical fire extinguishers which are a mess to clean up.
 

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Just have a handful of rags near and replace the pump with the engine cold, no fire risk whatsoever.
Regarding the fuel bleed, removing the fuse/relay is a good option, I'm sure that PIWIS has an option to stop the pump and going into replacement mode but if you don't have one the fuse out is the best way to do it.
 

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So I had this really cool 308 GTS 1979 Spyder Ferrari that I bought basically new back then. I was sort of a freak nick then. Motor was a little dusty. Why don't I Gunk it off? So I warm it up and then spray all this Gunk cut to maybe 80% with kerosene. Whom!!! If it was a rocket we would be T+1. I reach around and grab this huge extinguisher and pull the pin. It is full of all this white stuff. Fire goes out, but I was faced with a monumental cleal project. I am less fastidious now.




235777
 

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Thanks, SomeGuy, for the clarification. You're correct but, with HALON, all my bases are covered.
 

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I don’t know the correct Porsche procedure but if I was replacing I would either locate fuel pump fuse or relay and remove. Then start motor, it will stop when it has no fuel pressures remaining, or very little pressure.
Or wrap a rag around fitting to be loosened to catch fuel, there won’t be much volume of fuel released. Use compressed air to disperse fuel / fumes.
This is a DFI engine and it operates differently. This engine has a low pressure (approx 5 bar) pump in the fuel tank. Its main job is to supply fuel to the two HPFPs (one on each bank). Those pumps are mechanical and the pressure to the fuel rails is regulated according to demand. When the engine is shut off fuel pressure is removed.
 

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swingwing, do you know how long it takes for the high pressure side to bleed down? We're talking extremely high pressure here, right?
 
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