Replaced Oil Pressure Sensor, still no good

Hi all Just replaced my oil pressure sending unit tonight and went for a quick drive. Pressure was up to 5 bar for a bit until warmed up, then eventually settled around 2.5 at warm idle, then I pulled into the gas station and realized I was at 0 bar and it�s totally dead now. I removed and re installed the wiring on top of the sensor trying to make a better connection. No luck. could I have done something wrong with the install? a faulty part? Something else? realize the answer to all 3 of those questions is �possibly�, but hoping someone can steer me in the right direction. thanks. ETA: before changing the sending unit, the oil pressure gauge would stay pinned at between 4.5-5 bar constantly when engine running, and would be wherever it felt like being with the engine off. It also would fluctuate up and down when you turned the key. These were all signs of a faulty sending unit as I read online.

There�s a good possibility that it may be a faulty part. I replaced a functioning oil pressure sender with a genuine Porsche sender and it malfunctioned out of the box, never reading above 4.0bar. I replaced that with another genuine Porsche sender and it worked better, but wouldn�t read above 4.5 bar at cold start unless the engine is revved above 2k rpm. (I�m not sure whether this anomaly is with my engine or the sender, but I highly suspect it�s the sender since it never behaved like this with my original sender). With this I called it �good enough�, because I didn�t want to go through another episode of removing and returning the sender, but it really does irk my perfectionism. There�s another guy in the 996 Turbo forum who just posted a thread about his replacement oil pressure sender messing with the battery voltage system in his car. So yeah, I think you may have a low quality part (thanks Porsche). The biggest tell is whether you observe any difference between this oil pressure sender and your old one. If the behaviors are exactly the same, then would I begin to consider the car having an issue - whether it be the wiring or the instrument cluster.

Thank you for the response. I�m leaning towards a faulty part, but tomorrow I�m going to pick up some contact cleaner and see if that does anything. Also, I didn�t use a genuine Porsche part, I ordered it from ECS Tuning and it was an aftermarket brand �Hamburg-Technic�.

Hmmm� My opinion is that Hamburg-Technic parts can be questionable, but I don�t have any firsthand experience with them. It�s simply something I�ve concluded after reading on the internet. But, given my terrible experience with genuine Porsche oil pressure senders, it may be a better choice after all.

ECS does have the lifetime replacement, so I�m guessing that is the direction I will be taking if I can�t get the connectors cleaned well. the connectors aren�t exactly tight on there, they definitely wiggle around a bit, but it takes some force to pull them off.

I had a bad pressure sender (wouldn�t go to 5bar) and replacement part was also bad. Third one was the charm and readings are good now. I was even able return the faulty one. I would replace your new sender with another new one and return the faulty one.

Just a little oil pressure sensor trivia.... Oil pressure Sensors/senders work on resistance variable by a pressure diaphragm. They are sensitive. A little more resistance will make a reading change . As the oil pressure increases, the resistance of the sensor decreases. and as it decreases resistance increases. If any wiring is not perfect and is causing any added resistance the pressure reading will be effected. If 1 of the screw terminals is dirty or lose, or worn/corroded, is frayed or part shorted, the sensor reading will be affected. A perfectly good sensor could be reading wrong just from a wiring problem...

A "rough/dirty" test of the dash gauge ;;ie. with the wire disconnected the dash gauge should go up past 5 ...with the wire grounded to engine it should go all the way down... If it doesn't do this it means the wiring or dash meter is totally fubarred !!!

I hope you mean F�d Up But Also Repairable, my preferred definition of FUBAR. Which wire do I perform this test with? The larger or smaller?

Quotes source post: 20102214

You can actually do the quick test with both wires... With both disconnected you should see the the dash gauge go up above 5 and no warning light .. With both grounded to engine you should see the dash gauge go down to bottom and warning light come ON ..