'03 C4S Oil pressure gauge/sending unit

[bruce@fortetlc.com]

I'm experiencing an intermittent failure of "something" related to oil pressure sending unit or oil pressure gauge or (God forbid!) oil pump. Driving down the road and pressure goes to "0" and then bounces back up to "5" after a couple of seconds. It won't happen again for weeks and then do it again. I would think that if it were a sending unit the thing would just "go out" - same thing for the pump. Of course, when I take it in the mechanic he can't find anything wrong and no codes. Short of wholesale replacing parts has anyone experienced this?

thanks for any advice.

'03 C4S

30K miles.

[Ahsai]

Similar experience. Replaced the oil pressure sender and the problem is solved. Of course there could be other possibilities but most likely the sender is faulty.

I have a photo showing the new sender unit (on the passenger side of the car).

[demosan]

I'm experiencing an intermittent failure of "something" related to oil pressure sending unit or oil pressure gauge or (God forbid!) oil pump. Driving down the road and pressure goes to "0" and then bounces back up to "5" after a couple of seconds. It won't happen again for weeks and then do it again. I would think that if it were a sending unit the thing would just "go out" - same thing for the pump. Of course, when I take it in the mechanic he can't find anything wrong and no codes. Short of wholesale replacing parts has anyone experienced this?

thanks for any advice.

'03 C4S

30K miles.

bruce,

Could be as simple as electrical connections to the sender being loose/ intermittent. If connections OK, then the sender probably needs replacement.

Good luck!! demosan

[kpl]

mine was doing the same thing randomly. I just cleaned the electrical connections to the sender and it has worked fine even since. I'm surprised the connectors are not more weather/dust resistant.

[duuder]

mine was doing the same thing randomly. I just cleaned the electrical connections to the sender and it has worked fine even since. I'm surprised the connectors are not more weather/dust resistant.

how did you clean the connectors? i'm experiencing the same prob

[kpl]

pull the electrical connector off, use a small piece of sandpaper to clean the two contacts on the sending unit, put a dab of dielectric grease on each contact, reattach the plug.

[deckman]

I did the cleaning of the contacts, put the grease on and had one indicator failure last week. Yesterday it happened six times in two miles. What's the danger here? Does this unit actually regulate anything or just send the reading to the gauge in the dash?

I've been trying to get a replacement from SunCoast but they can seem to identify a part number. Does Porsche call this part an "oil pressure switch", part number 996 606 203 00?

Edited August 21, 2009 by deckman

[whall]

On the box: "Pressure Sensor - Engine Oil"; Part No. 996.606.203.01; MSRP : $56.31.

In the PET catalog: "Oil Pressure Switch"; Part No. 996.606.203.00

There are, as you know, two terminals on the oil pressure sensor/switch. The larger of the two sends a pressure signal to the oil pressure gauge in the instrument cluster, i.e., 0-5 bar. the smaller of the two terminals sends a signal to the low oil pressure idiot light just below the instrument cluster.

It is the idiot light that the DME monitors and records to memory. The oil pressure gauge is secondary. Either part of the oil pressure sensor/switch can fail internally - more likely the oil presure gauge portion. The idiot light portion just determines whether you have oil pressure or not.

If you have the proper amount of oil in the engine, without an illuminated low oil pressure idiot light, when the oil pressure gauge is fluctuating or dropping to zero, you are to "Have the fault remedied at an authorized Porsche dealer." If, however, you ever have an illuminated low oil pressure idiot light, you are to: "Immediately stop in a suitable place. Switch off the engine. Check oil level. If necessary, add engine oil.

Caution! Risk of engine damage. If the warning light comes on even though oil level is correct:

Do not continue driving. Have the fault remedied at the nearest authorized Porsche dealer.

Bill

Edited August 21, 2009 by whall

[deckman]

Thank you!!

[jgriffin56]

Exact same thing: replaced oil pressure sender...done over! 04 C4S Cab Tip