996 Turbo oil pressure

[mobhire]

I have a 2004 996 Turbo which has covered 48k well maintained miles, it has covered only 4k in the last 12 months without any probs, but I noticed last week on its weekly run that the oil pressure had dropped to 3 bar at 2800 rpm and when driven it would dip slightly, I stopped and checked the oil which had dropped one click. I then took to my fitter and got him to change the oil and filter which he said were fine, this made no difference to the reading. I was then advised to get the engine hot and leave running until the oil cooler fan came on then leave to go cold as he thought that the pressure valve in the sump may have been sticking. I could not believe that the next morning I used again and the pressure was back to normal as was my return journey home later that day, but alas the next morning it was down again so I repeated the getting hot routine but it has not worked since. Any thoughts!!

[lanan]

Apparently the oil pressure sender is known for this and randomly showing zero faults.
Possibly just a dirty connection to the sender unit, it is in a mucky area.

[Angelus]

I once had mine drop to zero, for no reason. I needed a lot of Fabreez to clear the seat after that. It sometimes fluctuates and I've been told it is the sender. I've got a quote of under £100 for a new pressure sender fitted from OPC, I'll get it done at the service next month.

[the other me]

Had mine dropping to zero (with a German warning which seemed to be "fault" ) whilst hooning. After the corner it recovered and oil level was OK, but still not too comforting.

[FarQue]

lanan said:

Apparently the oil pressure sender is known for this and randomly showing zero faults.
Possibly just a dirty connection to the sender unit, it is in a mucky area.

Just this lunchtime I was with a 996GT3 owner and a 996tt owner and they both mentioned that their oil-pressure dipped every so often. Mr GT3 said his car had done it for some time and suggested it was a sender problem rather than an indication of impending engine doom.

[Rockster]

mobhire said:

I have a 2004 996 Turbo which has covered 48k well maintained miles, it has covered only 4k in the last 12 months without any probs, but I noticed last week on its weekly run that the oil pressure had dropped to 3 bar at 2800 rpm and when driven it would dip slightly, I stopped and checked the oil which had dropped one click. I then took to my fitter and got him to change the oil and filter which he said were fine, this made no difference to the reading. I was then advised to get the engine hot and leave running until the oil cooler fan came on then leave to go cold as he thought that the pressure valve in the sump may have been sticking. I could not believe that the next morning I used again and the pressure was back to normal as was my return journey home later that day, but alas the next morning it was down again so I repeated the getting hot routine but it has not worked since. Any thoughts!!

Whenever there a strong suspicion about oil pressure one has to start at the oil pump and verify it is putting out the right oil pressure so you should have had your fitter do a real oil pressure test just to be sure the oil pressure was ok. But it probably is or you'd know about it now.

As others have said the oil pressure sender is often suspect in these seemingly odd ball oil pressure reading oddities.

I've never seen the oil pressure drop from around 4.5 bar to 3 bar at 2800 rpm other than perhaps for a brief instant of time as the oil pressure gage needle does flick and flit back and forth a bit and random times. I asked my tech about this and he said it is a connector/connection problem, most of the time.

There is always the chance that there is something amiss in the oil pressure relief valve or a oil intake (the oil pump is getting air) or the engine oil level is low and the engine oil is heavily aerated. These though are very rare conditions.

Lastly I assume you are running some approved oil of the proper viscosity grade and not some light duty sewing machine oil or the like?

Sincerely,

Rockster.

[Sunnysidebb]

My sender failed as well, doing 70+ on the m6, no oil pressure warning light and plenty of oil in the engine.
Porsche replace sender under warranty and it was fine afterwards.

[NBTBRV8]

Another 996t owner here that has had the oil pressure sensor replaced.

[monthefish]

And me.

Randomly dropping to zero (triggering the dash warning in the process) but then going back to normal pressure after about a second.

Don't worry too much, as if you think about it, a catastrophic engine oil pressure faiulre would have been a blown seal (or something else) in the engine, and if that occured it wouldn't be able to self-repair and reinstate the original pressure.

Like many, mine was a simple sensor failure (fixed under warranty) and has been perfect since the fix around a year/5,000 miles ago.

Angelus said:

I once had mine drop to zero, for no reason. I needed a lot of Fabreez to clear the seat after that.

I can identify with this. First time it happens it's a horrible feeling.

[marky911]

Interesting reading this. I think I'll have my indy fit a new sender at my spring service. It can't hurt just to chuck a new one on.