ianellison

Have you ever accidentally overfilled your car with oil? How much was it over the max mark on the dipstick when you checked on idle at the engines normal operating temperature? If you ran the car before you found it what happened?

Smokin

This is a common mistake and needs to be fixed before you drive the car too much. (If at all) You can do a search on this and you'll turn up a ton of useful info. Peopl have overfilled their engines from anywhere from a few ounces to several quarts. You need to make sure that the oil level is in between the two marks on the dipstick. Running with too much oil can mess up your mass airflow sensor, intakes and a few other items... Drain your oil to the recommended level!

DaveK

I haven't done it - but reputable service centres have (two different ones in fact). As for what happened, I thought : It's not that overfilled, sure I'll be OK.

And 2 weeks later was cleaning my AFM / ISV because my idle was screwed.

TR6

Be certain that the engine is at full operating temperature (sound of oil cooler thermostat kicking on) AND idling for at least a minute when you check that dipstick level. The dipstick should be checked with the engine idling. This seems to be the mistake often made from the threads I've researched on this common problem. As others have noted, you cannot even assume that your mechanic knows this. Best to remind and double check.

Can you tell I'm a little paranoid about this? So far, I've not overfilled the oil (knock on wood).

Indycam

"Have you ever accidentally overfilled your car with oil?"
Yes I stupidly overfilled the thing . On a quick right hand turn the extra oil went down a tube into the intake system , the exhaust blew a huge cloud of smoke , the engine knocked like a sob .
Did ya know that oil has a low octane number ?
The funny thing is it didn't peg the needle , the needle was up in the high end of the range when hot , but not showing an overfill.
Now I keep it at the low end of the gauge when hot .

TR6

Which brings up something I've been wondering about... My oil level guage rarely moves from the bottom reading. But once in a while at idle (I think) when its hot (say, in stop and go traffic), the needle will rise to somewhere in between the bottom and top for a bit, but the next time I rev the engine to move forward, it drops back down to the bottom. When, exactly, is the needle supposed to accurately indicate the oil level? The dipstick shows the oil in the proper range (between the two marks at warm idle).

Marc Shaw

It should read at the halfway mark or just below once the car is at operating temperature (ie. hot and with the oil thermostat open) and the car idling for a few minutes on level ground -- ie. the same time you are reading the dipstick.

A thread here a little while back seemed to show that most people here put more faith in the gauge than the dipstick -- me, I removed the dipstick to save weight.

Marc

BongoBradley

It appears from my searches that many, many people have done this. I think I now have the same problem. The gauge was just coming up above the bottom mark maybe suggesting something like 1/4 full if I can read a gauge correctly. The dipstick showed what I thought was a mark just at the bottom line. So I carefully added a half quart. The gauge came up just a little and the dipstick still showed only on the bottom. So I added another 1/4 -- same thing. So then I added the rest. Then the gauge went up nearer to what I would consider 3/4's yet the dipstick still shows basically empty.
Who designed this system? Now I have to take it to my mechanic just to check my own stupidity. How embarassing is that? At least it seems that I'm not the only one to have ever had this problem...

last toy

If a Porsche shop tech does not know to check oil level with the car at idle and running temp, run don't walk away from that shop. You have to check the dip stick to get the safest reading, the gauge is more of an idiot warning than anything else. It also is meaningless when the car is in motion, the car should be idling in park, this is a 911 quirk not just 964's. The common problem with 911 dipsticks is the difficulty reading it. The underside can look like its overfilled when the top side of the dipstick shows a low reading. The top side should be the right reading but it's still safer to add oil little at a time and see if the top side mark moves up and the bottom side stays the same.

Chad T

Another thing to keep in mind is that the FULL range of the guage is one quart. Same thing with the dipstick. The high and low marks represent only one quart. It's very easy to overfill.

TR6

Not sure if you guys would agree with this or not, but another 964 buddy of mine told me, when in doubt, err on the low side. He said there is plenty of oil capacity in the system so there is adequate safety margin on the low side and its better to be a little low than a little too high. But don't take my word for it, I know barely enough about these cars to be dangerous...

Eggplant Cab

Marc if I remember correctly, most of those opinions don't say they don't trust the dipstick, they just can't read it and don't trust themselves.

I've had 2 "porsche" mechanics over fill the oil. I'm too lazy nowadays to do it myself. But I just give them 8 quarts and fill the rest myself at home. And it's only a every 15k or 18mths anyhow. Afterall with consumption at 1 quart per 2k miles, I figure the oil is 3/4 changed already by the time you have to do the filter. LOL

Bearclaw

Yeah, by almost half a quart.

Nothing. That was 1200 miles ago.

Marc Shaw

True - the majority who answered the poll used both - "oil-itis" (p-car lube anxiety disorder, DSM-IV).

Marc

Indycam

"Which brings up something I've been wondering about... My oil level guage rarely moves from the bottom reading. But once in a while at idle (I think) when its hot (say, in stop and go traffic), the needle will rise to somewhere in between the bottom and top for a bit, but the next time I rev the engine to move forward, it drops back down to the bottom. When, exactly, is the needle supposed to accurately indicate the oil level? The dipstick shows the oil in the proper range (between the two marks at warm idle)."

Thats normal . The gauge is nothing until the motors v hot , at idle , on flat ground .
I got stuck behind an accident on a freeway in hawaii , miles of very slow stop and go , much more stop than go , engine temp went way way up as did the oil level .