993 - oil consumption

[Schnellmann]

About 6 months back I bought a 993 with just 38'000 km. Got it from an OPC. Based on documented history and condition (looks and drives almost like new) I am convinced the mileage is genuine. I was therefore really surprised when it used a liter of oil in around 1500 km. I know that is within the tolerance range quoted by Porsche but surprising for an engine with such low mileage.

Should I be concerned?

[Pugley]

I guess that the youngest 993 would be more than 12 years old now.

I would expect that valve guide oil seals may have become hardened after that many years. Some components deteriorate with age whilst others wear with use.

A higher mileage engine may have had a minor rebuild by now and hence would have had any age related parts refreshed.

Its swings and roundabouts really. Some bits wear, some bit age.

[SunDiver]

NA or turbo?

[Pickled Piper]

How did you measure the oil level? Dipstick or gauge? The level is also very sensitive to the incline that the car is parked on.

In short did you measure in exactly the same way each time?

PP

[mollytherocker]

Mine has nearly 100k miles on it and 'uses' virtually nothing. In 5 years I have put half a litre in it twice.

These engines thrive on use, and I would suggest that it needs a proper 'run'.

Le Mans should do it.

MTR

[Schnellmann]

In answer to the questions:

NA

Car had service when I bought it. I didn't check the oil level myself but when the garage swapped the winter tyres for summer tyres they checked and had to add a liter. I only realized they had done so when I saw the invoice. Since then I have checked with the gauge and it seems to have used some since then. I am going to measure it more accurately now.

My first 993, many years back, had high miles and used lots of oil. My other 993 with 130'000 km uses no oil.

[stewart rix]

Unless you're seeing plenty of blue smoke (not just a quick puff on start up), then it's unlikly to be oil getting into the combustion chambers (valve guides etc). You may have one or more leaking cam cover gaskets or perhaps one of your oil filters has failed (rusted through) or is leaking. You won't necessarily see a pool of oil under the car because it tends to collect in the undertray, being dropped as you drive along.

Edited by stewart rix on Thursday 17th May 14:36

[kitesurfer2]

Mine uses vitually none at 140000 miles.Must be something awry.

[supersport]

Pugley said:

I guess that the youngest 993 would be more than 12 years old now.

I would expect that valve guide oil seals may have become hardened after that many years. Some components deteriorate with age whilst others wear with use.

A higher mileage engine may have had a minor rebuild by now and hence would have had any age related parts refreshed.

Its swings and roundabouts really. Some bits wear, some bit age.

I don't think that's it. My 1987 3.2 uses barely no oil, just a small top once a year and at the end of each year the oil looks like new. Although the manual quotes up to a 1l per 1500KM (or something like) I don't know anyone who actually uses that (other than my 87 944 with 205,0000 miles on it.)

[monthefish]

kitesurfer2 said:

Mine uses vitually none at 140000 miles.Must be something awry.

Schnellmann said:

I know that is within the tolerance range quoted by Porsche

[ras62]

You dont have a baseline at the moment so I would monitor the consumption for a while, it is important to do it with the engine fully hot i.e temp gauge horizontal and front wing hot to touch. Some oil consumption is nothing to be concerned about.

[anonymous-user]

mollytherocker said:

These engines thrive on use, and I would suggest that it needs a proper 'run'.

Le Mans should do it.

MTR

This.

I got told be a specialist that it's the low mileage ones you should be worried about rather than the cars that are given a good run daily or weekly.

Mine uses about half a litre every 1000 miles or so, maybe a bit less.