deptotpr

I looked at a beautiful pearl-white 87' S4 today, which has been sitting for a year. Trust me, when I say, you do not want to see a picture; as you will be lured in. Just read the facts. The exterior was immaculate, interior good. It seemed to be running rich, initial hard start, with some dark smoke. It seemed the air-ratio needed adjust, as off a little. However, what concerns me is an inspection of the oil level, revealed gasoline on the dipstick. Simple fix with a complete oil drain, and refill; or should I just simply run away?
I am requesting a diagnosis of how gasoline gets in the oil, and is it considered a major disaster, or engine is done? All comments are encouraged.

928 at last

First thing I would do is drain and refill with fresh and a new filter, then run for a few miles (say a couple of tanks of gas) while keeping an eye on things and then do a compression test. Only way I know of fuel getting in the oil in any quantity is by bypassing the rings.

heinrich

Ka...... booommmmm?

Tony

I would think that the gas would just about mix right in with the oil? Sure it isnt water?

Speedtoys

Needs a lot of work in sensors/injectors to get that running right.

Its running SO rich, and never really warmed up, that the cylinders are being washed down in multiple cold runs, and fuel is condensing in the crankcase.

Fixable..but only once you own it and do the needful on the deferred standard maintenance.

WICruiser

You say it has been sitting for a year, but does that mean never run or never run long enough to go anywhere. If the car is started run for a few minutes to relocate or just to show that it runs and then is shut down the engine never gets warm and is always running in cold start - rich mode.

As said by Speedtoys it needs to be diagnosed and may require some corrections.

If the car starts easily and you can run it for at least 30 minutes - preferably on the road to get some load - so that water and oil temperatures get up to normal, you will get a much better picture of the condition.

Mrmerlin

FWIW gas in the oil isnt a deal breaker, it was SOP to add gas to the oil of aircraft engines before shutdown in cold climates this woulod reduce the viscosity of the oil and allow restarting easier when the engine was cold.
The gas would eventually evaporate when the engine was run again.

That said you might find a leaking fuel injector also the fuel dampers and FPR should be inspected by pulling off the vacuum lines to smell for fuel

Speedtoys

Ya...yer probly onto a "good car", just factor in about $4k in quick work to do once you have it. (top end, front end, sensors, electrical clean up.


Then drive the ever loving **** out of it.

..seriously. It _does_ heal neglected Porsches.

z driver 88t

If its been sitting a long time its very possible it just leaked from the injectors and settled into the pan. When you turn off the car the fuel rail and injectors are still pressurized to around 40 psi (at least on my Z car). In theory the injectors should be sealed and should not leak but I wouldn't be surprised if one or more had a slow leak. And then it would gradually drain into cylinder, down the wall and settle in the pan. I would change the oil and if you have access to a wide band O2 see what mixture you're getting to make sure its not running too rich as well.

I would not think this is necessarily a deal killer. There's really only a few ways I can think of that would get oil into the pan. Unless the car is just running super rich, lots of black smoke, my first thought is one or more faulty injectors.

I see you're in Tampa. I have the fuel pressure guage from Roger that mounts to the fuel rail. I'm in Gainesville. If you like I'd be glad to send you the guage to borrow. You could mount the guage, start the car and run it for a few seconds just to pressurize the system. Then let it sit for a few hours and see if the guage hold pressure or if it bleeds down quickly then I would bet its coming from a leaking injector.

Speedtoys

Theres not a TON of fuel in the injectors to leak down and have measurable fuel in the pan..most of it is leaking back thru the pump.

it'd have to be a lot of on/off with a very leaky few injectors to do that.

vze2jshn

Wouldn't a leaky injector(s) manifest itself with a misfire through the exhaust upon start up?

WallyP

Probably not. A slow leak in an injector makes virtually no difference while running.

Jim Devine

Before you buy it, take it to a smog check station.
If it's way off it would show up on the print out.

Also consider getting an oil sample kit from Blackstone Labs & send it in. Their report will show
a lot such as bearing material etc. Well worth the money & quick turn around.
Click on the gas/diesel button to see a sample report and what is covered:

http://www.blackstone-labs.com/report-explanation.php

The cost of both tests combined shouldn't be
more than around $75 or so, a lot cheaper than repair shop time.

JHowell37

I'm not sure how you could determine that gas is getting into the oil since gasoline readily mixes mixes with oil. Was the oil just very thin? I wouldn't worry about it too much especially if you said the car is running rich. As for the car running rich and being hard to start, I'd bet on a bad MAF.

All engines experience some degree of fuel leakage past the cylinder rings. It usually evaporates and gets vented back to the intake. But if the engine is run a lot without fully heating up, the excess fuel doesn't get a chance to evaporate, but it will if the engine is run long enough.

I would speculate a bad MAF, and a lot of flooding due to it being hard to start. Depending on the price, I'd buy it without further investigation until I got it home.

dcrasta

Depending on your budget and their asking price, if the rest of it is in as good condition take a chance. Fuel in the oil can only come from one place, and if this car has the original pintle injectors they can stick. I have had mitsubishis do this and the injector would never fully close (think a small stream of fuel) . A bad CTS can also cause rich conditions. I would do a PPI (including compression and leakdown testing). As long as the sealing of the Combustion chambers is good and the bearings are sound you can fix a fueling issue.