Oil consumption in a 986 Boxster S

[peterbredde]

Hi Guys. I am looking at a 2003 Boxster S that has only 66,000 kms on it. The car seems solid and the interior is nothing short of spectacular for a car of this age so I think it's been taken care of. The only issue I am worried about is that the owner told me yesterday (very casually) that it seems to use oil. It had only done 3,000 kms since the last service and the oil level was at half.

I checked under the car and there were no signs of leakage. Should I be worried?

[911944]

Not really.

Who's to say the oil was set to the perfect level when last serviced?

All cars consume a bit of oil

[mollytherocker]

I am wondering why the owner feels it necessary to tell you that the car 'uses some oil'?

I think you need to ask some more searching questions.

[edc]

8k since March in my 986S, one service in the summer but never had to top up the oil. I would have suggested RMS, but you say everything is clean. I take it there are no signs of oil in the coolant.

[Pugley]

"HOW MUCH" oil consumption is safe will continue to be an eternal argument!

I have owned 2 water cooled 911s and neither used any significant amount of oil. I am also aware that some cars do use oil with no detrimental effect.

Given that oil consumption and carbonisation/over heating of the pistons seems to be a precursor to scoring/cracking of the bores in this series of engine, I would be cautious of buying a car that was starting to get through half its oil level in 3000Kms.

Perhaps a bore inspection would be the safest way to clear any doubt?

[peterbredde]

The guy only mentioned the oil when I asked about servicing intervals. At the time it didnt worry me too much as my old V6 Galant used to lap the stuff up like nobody's business (even from new) and I ran that car for 6 years without the slightes problem or any increase in oil consumption.

I didn't check the coolant.

Thanks for the responses

[Chrisp5782]

I think I'd give this one a miss, that's BIG oil consumption. My 986 never used a drop between services and it was driven every day.

Check for soot around the left hand side exhaust as was previously mentioned it could be an indicator of scored bores.

If it were my money I'd be looking elsewhere.

Edited by Chrisp5782 on Monday 24th December 14:04

[Trev450]

I think I would walk away from this one unless you are prepared to pay for a bore inspection. As has been said, some of these do use a bit of oil but not as much as you have indicated.

I had a 350Z for 4 years from new and it used 1 ltr of oil per 1000 miles from day one. The Boxster/Cayman engine generally does not use much oil and as an example my 5 year old 38000 mile Cayman S has used absolutely none between services during the last 3 years of my ownership.

[anonymous-user]

Pugley said:

"HOW MUCH" oil consumption is safe will continue to be an eternal argument!

I have owned 2 water cooled 911s and neither used any significant amount of oil. I am also aware that some cars do use oil with no detrimental effect.

Given that oil consumption and carbonisation/over heating of the pistons seems to be a precursor to scoring/cracking of the bores in this series of engine, I would be cautious of buying a car that was starting to get through half its oil level in 3000Kms.

Perhaps a bore inspection would be the safest way to clear any doubt?

It has not burned half it's oil - just halfway down the dipstick which equals half a litre or thereabouts.

[falkster]

Other than annual oil changes, my wife's 986S has never been topped up in 5 years.

[Rockster]

peterbredde said:

Hi Guys. I am looking at a 2003 Boxster S that has only 66,000 kms on it. The car seems solid and the interior is nothing short of spectacular for a car of this age so I think it's been taken care of. The only issue I am worried about is that the owner told me yesterday (very casually) that it seems to use oil. It had only done 3,000 kms since the last service and the oil level was at half.

I checked under the car and there were no signs of leakage. Should I be worried?

Assuming the oil level was full at the start of the 3000kms 0.8 liters of oil has been consumed. If you read the owners manual carefully the max. allowable oil consumption is 1 liter every 1000kms. The engine of the car you are considering is using way less than that amount of oil.

If you want, and it may not be a bad idea, query the current owner for more details about the engine's oil consumption. Ask him how he drives the car? Lots of in town driving with an occasional longer road trip? Or does he buzz the engine to redline often?

If the car checks out fine, and if after you take a 15+ mile test ride followed by a 15+ mile test drive and the engine through all phases of this from cold start, cold idle, to warm then hot idle and running up to redline (once fully warmed up) shows no signs of issues then I think you have nothing to worry about.

You have to be careful about comparing oil consumption numbers. They can be I have to say it unreliable. A person drives around and the oil level remains unchanged. The engine uses oil, but because of the type of driving the oil loss is made up for by the build up of water and unburned gasoline.

This same driver can then see his engine exhibit a big increase in oil consumption if he takes the car out and drives it differently than his usual pattern. The water and unburned fuel boil away and the oil level drops and this looks like a big increase in oil consumption.

The other side is the driver spends a lot of time idling the engine or pushing it hard all the time, up to redline. The engine naturally burns more oil and the engine could be -- depending upon the amount of oil consumed -- an oil burner. But in the hands of a driver who doesn't use the car in this fashion the engine's oil consumption drops to a less scary level.