S4drifter

Posting here for a quick response about my 930. generic 911 question.

I am a Newbie and while not mechanically dis-inclined, I am new to this car. My car came back from a full service last month. First time I took it out, I ran it for about an hour and a half on a spirited back road run. at the end of the run, my engine was surging and almost stalling. car was also blowing some black smoke, not thick, but still there. I let the car cool down and while I was idling in the garage, the idle smoothed out noticably.

So I let it sit for a week.

Took it out again tonight and had the same thing. Noticed that the druck pressure raised and lowered with the surges. 3 hours later, on a whim, I went out and checked the oil. THe dipstick was dry and it appeared that there was condensation on the inside of the cap. Can this be right? If the engine is cool (slightly warm) shouldn't the dipstick, still show some oil?

I am suddenly afraid, I have been driving this thing with no oil. Car just came back from a $2,000 service. I am hoping that the oil just settles in the pan once the engine cools and the dipstick shows nothing. If not I am about to make a very angry phone call.

There is no oil on my garage floor.

Finally, could this be causing my surging engine and black (and very noxious by the way) exhaust?

Any help is appreciated!

ron mcatee

If the oil level is correct, when the engine is hot, the oil level should be between the min and max fill lines. Did the service place fill the oil tank? I would be suspect since it was recently done.

S4drifter

My thoughts exactly. Should the dipstick show anything if the engine is cool?

Juan

I remember something nhaving been said nabout the "sump drain" (??) can be installed incorrectly. Happened to my 78 years ago now and was an easy fix. If I remember correctly you did the right thing by letting it cool down before driving it.

993chaz

You need to check the oil level at the correct operating temperature. The level should read somewhere between the 2 fill lines.
You can't get an accurate read on a cold engine.

911S4

The correct way to check the engine oil in an air cooled 911 is with the car on level ground with the engine running at normal operating temp. 180-200 degrees. It should read 1/2 way between the marks on the dipstick. With a cold oil temp and the car shut off it is normal to not see any oil on the dipstick. Surging on a K-Jetronic 930 is normally due to an air leak somewhere in the intake side, or improperly adjusted Air/Fuel ratio. Did the shop adjust the mixture incorrectly? Did the shop adjust the Valve lash (valve adjustment) incorrectly? Other things that can cause problems similar to what you have described is a leaking cold start valve or faulty auxiliary air valve. Druct pressure is the Oil presssure in Bar not PSI and it will increase and decrease as the engine surges.

911S4

One more thing I forgot to mention. When shops remove the intercooler from 78-89 CIS turbos, the orange rubber O rings (one from the turbo and one on the throttle body often get ripped if the mechanic is not paying attention to what he is doing when reinstalling the intercooler. That is another area for a leak. Does the car make full boost? In 3rd gear at full throttle it should read .8 bar on the gauge.