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Porsche Fuel Pump Troubleshooting

Can your defective Porsche fuel pump be repaired? How best can you check the condition of your fuel pump? The fuel pump needs to be in peak operating condition for an engine to run efficiently. Because of their location, Porsche fuel pump problems are difficult to diagnose. When up against one, it pays to ask an Expert to help.

Read below were Experts have provided answers to some users’ fuel pump questions.

Is it okay to install used replacement fuel pumps on a Porsche when the exact selection is not known?

Considering the significance of the fuel pump it is not worth it to install used fuel pumps. If unsure about the type of fuel pumps to use, take the VIN number to a dealer who will advise the correct part numbers.

Where could a sporadic high-pitched whine near the gas tank intake of a Porsche Boxster come from, and what can be done about it?

If this is coming near the fuel intake or in the vicinity of the fuel tank it could be the first signs of failure from a fuel pump. However, this would need to be checked further to be certain the fuel pump is going bad. If it is, the solution is to replace it.

Why would a Porsche Cayenne suddenly lose power and speed?

This could happen for multiple reasons which include faulty wiring or connections to airflow meter, crank or cam position sensor, throttle position sensor or oxygen sensors. It could also be caused by poor connections to the fuel pump. All connections would need to be removed and cleaned with a squirt of contact cleaner.

Why would a Porsche Carrera stop abruptly when on the freeway then start again a half hour later?

Chances are that the problem is fuel pump or ignition related but more likely to be a weak pump. A failing fuel pump sometimes does shut down when heated up then starts again after it has cooled down. Turn off the ignition then turn it on again and listen carefully for the hum of the fuel pump which might last just a second or two. There is no definite way to check the condition of the fuel pump except for a fuel pressure test. If the pump is proved to be weak or failing, it will need to be replaced.

Why does a Porsche Cayenne keep starting then stop after about 10 seconds?

This is a fairly common fuel pump problem. Check it out by connecting a fuel pressure gauge and observing the fuel pressure readings. The fuel pressure will drop abruptly which indicates that the fuel pumps below the rear seat are beginning to fail.

The fuel pump on a Porsche 911 is working, but why isn’t fuel reaching the injectors?

It sounds very much like insufficient pressure being delivered by the fuel pump in the tank. This could happen if the connections to the pump are damaged or corroded in which case the pump will never reach its operating speed and so, not be able to develop its rated fuel pressure. At worst the pump could stop entirely. Check the fuel pressure at the inlet to the primary engine fuel distributor. Ideally, fuel pressure should fall between 5 and 5.8 bar. If it’s anything less the fuel pump will need to be checked. Before replacing the pump check the fuel filter which could be clogged and would have the same effect. If both are good then the fuel distributor as the fuel metering pin might be stuck. If this too is good then the injectors will need to be removed and checked. All injectors should spray simultaneously and equally. If this is not so then the injectors might need to be ultrasonically cleaned or, if defective, replaced.

How to troubleshoot a Porsche Cayenne which shuts off after about 5-10 seconds?

The most common reason for this to happen would be a failed fuel pump. This can be verified by pulling out a fuse so only one pump runs the engine. If the fuel pump is proved to be bad it will need to be replaced along with the fuel filter. This is a tricky job because the pumps are installed at the bottom of the fuel tank.

It’s difficult to tell if your fuel pump is not able to deliver at the right pressure. But this is where an Expert can help on reading the symptoms. Asking an Expert to help with a fuel pump problem is a wise decision which can save much time and money. The advantage with Experts is that they can be reached when you need them most.

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