OJ GTS

Hello all

Last year, covering when I was commuting about 55 miles at high speed each way to work, my GTS was using about a litre (near enough a quart for the non-metric) every 500 miles. I covered 5 or 6k doing that, not really concerned as the GTS has a reputation for using oil and usage has been consistent since Dad bought it in 1998.

Referring to the previous owner (Dad), he'd topped it up with a litre about every month, when he was commuting into London, on about 20 miles a day in heavy traffic, so slightly less usage mile for mile.

Recently, it's almost completely stopped using oil (and no it's not empty ). I've covered about 1000 miles over the last few weeks and it's barely moved off the top notch of the dipstick.

Is it broken?

Oil brand hasn't changed (and I'm not starting that one), the only thing that's different is the weather (car was last used in the summer and it's now still cool here in the UK), and the HVAC has been refurbished having never worked properly with the 'main valve' being replaced (forgive me for not knowing its proper name).

The car went through a period where I was starting to get worried, using about a litre of oil every 300 miles, but I put it down to a particularly hot week where I spent a lot of time booting it about on the motorway driving to circuits and sponsors. I got someone to drive behind me while I floored it, and they witnessed a puff of black/grey smoke on accel.

Theories so far at work (powertrain engineering) have been:

a) Broken Valve on HVAC was upsetting the crankcase breathing somehow

b) Old man drove it like... err... an old man (unlikely) and my heavy right foot has finally deglazed the bores/seated the rings/whatever

c) Worn out MAF (soon to be checked) is overfuelling on hot summer's days and causing bore wash, but in cold, dense winter air it's about right.

Any other suggestions, opinions on likely causes welcomed

pcar928fan

If the car is running well, just count yourself lucky. None of the things you describe should have any impact on how or why a GTS burns more oil than an S4. FOR SURE they burn more when you are running them hard! A track weekend will EASILY burn over a quart in a GTS.

SteveG

I vote for "b", with editing. I thought the GTS consumption was blowby, so I would think it might affect valves and be evidenced on the plugs. If so, there would still be evidence there. Otherwise I'd join James and just enjoy the circumstance.

OBehave

Maybe your out of oil.

9two8

{QUOTE= .., it's almost completely stopped using oil (and no it's not empty ).
-----------------------

Ken
80 928 S
5 Speed

UK

OBehave

Yeah I know,guilty as charged.I thought I had that" Post first,Read later" thing under control.I will work harder to fix that.

Leon Speed

High rpm's cause a lot of blow by. Drive it in an easy going manner, you can go a long way without having to add oil. It is that simple (well except for the part about driving it in an easy going manner ).

Charley B

Not the first time I have heard of a GTS using much less oil after mileage has accumulated between 50K and 100K miles. Mine improved appreciably between 50K and 60K but I was trying different oils and viscosities so I have no way of knowing where the results come from.

Tom. M

You must be measuring wrong because it's a known fact that all GTS' burn massive quantities of oil..I've not seen one that doesn't


Waiting patiently for Chuck Z to chime in

dprantl

Of course... it even says so in the owner's manual

Dan
'91 928GT S/C 475hp/460lb.ft

andy-gts

could the oil be diluted with gas possibly?

Charley B

Ye bastids!

AO

Thank god I'm not the only one with that affliction...

soontobered84

Mine uses virtually no oil ....201,000 on the odo.

Freaked me out intitally.

ROG100

Seen an improvement with mine after 120k.
The ProVent helps as well.
Roger