dcdude

I test drove a car this weekend. The oil pressure seemed high (4 to 5 all the time), temp was well below average, but the oil level(?) on the left was in the red. He pointed out that he had an oil leak. He previously replaced one valve cover gasket, and guessed he might need the other now. Car's going in the shop tomorrow to address this.

So there's reason to believe the level really is low. Can you drive with this gauge reading in the red? I know you need to warm up for at least 30 seconds to get a good reading, but it never rose up. Owner says "it holds 11 quarts, no big deal." If it was my car, I would have added a qt. before leaving the garage. Hmmm...

I know there's a risk from overfilling, but is this the sign of a lazy, sloppy owner or am I being ****?

ca993twin

Getting a proper reading of oil level on a 911 is pretty tricky. Most of the time, the gauge is fairly accurate, but the dipstick is better. Either way, the oil level can ONLY be read when the car is frigging HOT, level, and at idle. The gauge, from top to bottom is only the last quart or so, and with the big oil tank, normally not a big deal. And when I say hot... I mean HOT, not warm.

amfp

Check oil with dip stick when engine is warm with temp is in center of guage. Do it on level ground. The gauge can be sensitive at times and needs be reconfirmed with dipstick. I would not worry about it being a quart under, it is much better to be a little low than a little high. I try to keep my oil reading between the lines, or about 1/2 down. Seems PO is correct, and replacing gasket is no big deal. These usually got replaced with valves were adjusted with prior 993's. So after 10 years, new gaskets are just a wear item.

I would be more concerned with maintenance records, prior oil changes, and a tech that really knows these cars. They are not inexpensive to bring up to the highest standards. Good luck.

DJF1

gasket is no big deal. The gauge measures about the last quart only. It does not measure the overall oil in the car, so if its on red chances are that there could still be well over 10 quarts of oil in there.
Furthermore when you drive the gauge is useless. It only works stoped, at idle and on a level surface. Finally the oil expands, so while you may start your day with the level on red, by the end of the ride if you are on a DE or stop and go traffic the needle could be registering full... 30 seconds is certainly not enough starting from cold. More like 10 minutes on idle....
Check only the dipstick to ensure you have proper oil in the car. If you start the car in the morning and you see the gauge in red and you go to put a quart in there, prepare yourself for a major oil overfill, read a big MESS
Welcome to the 911 club

deltawedge

The pressure when warm at idle (a bit past 8 o'clock) should be 2-2.5 at idle (~800rpm) and 2.5 or more at 2500 rpm. The pressure cold should be 5 right after a cold start. This is normal and no cause for alarm.

Pressure below 2 when warm at idle would indicate a good time to verify the pressure with an external gauge (the senders can get flakey at low pressures).

On your next oil change pour about 6 quarts of oil in slowy with the engine off. Then start the engine and add 3 more quarts slowly (assumes you drained both the oil tank and sump). If you pour too fast, you will cover your passenger side heat exchanger with oil and the smoke plume will notify you of this fact. Drive the car until about 9 o'clock on the temp and slowy add oil until you get a reading on the dipstick about half way up the twisted section of the dipstick. At this point, the gauge should read about half way (assuming the gauge and sender are working).

John Velasco

Do you want a car with a Knowladgeable owner. Whats your budget? Call 626.446.3500 ('97 C4S).

95 C4 993

I have learned not to pay attention to the gauges, although they are indicators for me. When my dipstick registers between 1/2 and 3/4, its fine. That usually puts me between 8 (1/2) and 9 (3/4) o'clock. Give or take a couple of minutes on the clock.

John Velasco

My gauge works after the temp moves up between the 8 o'clock and 9 o'clock hash marks and then only when cruising or stoped on level ground.

jv

Peter B

After a recent oil change/service service the mechanic drove the car for about 15 minutes then returned, parked and kept the engine revs at 4000 for about 10 minutes until the temp gauge was reading "quarter to". At tickover the oil gauge read half way up. He also checked the off-side sills to see if they were getting really warm (oil flow/return to rad in front wing)
Me, being a grade one pillock, had previously overfilled the resevoir without getting the engine bl**dy hot and consequently blew the RMS. A £600 lesson learned.