Sorry brother, I have never heard of such a thing. My only 997.1 was a Turbo and it did not burn any oil either. I had no idea the .1s were burning that much oil. My 996tts didn't burn oil and drove the **** out of those and put up to 80k miles on them.

 

to be fair there is a big difference between what porsche find "acceptable" and what is "normal". Almost all manufacturers have this 1qt/1000 mile acceptability that gives them wiggle room for the variances in oil consumption a car can have from how it is driven, type of oil used, how it was broken in or is wearing, etc. It frees them from warranty repairs of pistons and rings on moderate to light oil burners


That doesnt mean most of us see 1qt usage every 1k miles. Id bet there is more like 1 in 100 of us burning that much oil on a non track car. Its also not a 997.1 vs 997.2 issue. The same "acceptability" from porsche is likely even in the 991 cars. I have a 997 with 70k miles and definitely dont burn a quart every 1k miles or even every 3k miles.

mike

 

 

Yup. The maximum permissible consumption is 1.5 liers per 622 mi per Porsche's TSB on consumption.

EDIT: Did not see the bulletin posted above :-) Someone beat me to it.

 

Do you have any ticking when the engine is hot. Would be worse above idle but below 3000 rpm? Is one tailpipe sootier than the other? Was this from bank 2?

You can't check for early signs of bore scoring unless you scope the cylinder with the piston at TDC and go in through the sump area to inspect the bottom of the bores.

 

Hey Charles, Appreciate your insight and input over the years from LN engineering.

Could you share some wisdom and elaborate just a bit more on why you ask about "ticking" above idle, but below 3000 rpm?? What mechanically are you looking to know or find out? Is it a constant ticking, sporadic, how loud, tell tale signs, or does oil brand or viscosity make a difference???? etc, etc. Any info is greatly appreciated to increase our awareness. Thanks!

 

Where lifters or tensioner noise usually will quiet up as oil pressure increases above idle engine speeds, piston noise that comes with the increased piston to cylinder clearance resulting from scored bores will be most noticeable above idle and below 3000 rpm. It would sound very similar to a lifter tick and is often mistaken as bad lifters. Sounds similar to injector noise or an exhaust leak to the untrained ear. Piston slap will only get worse as the oil gets warmer and won't go away, where lifters usually will quiet up and can be more intermittent.

Thicker oil will mask the problem as it provides more cushion, but ring seal will eventually be compromised on those cylinders that are scored enough that you will get a CEL for misfires and you will typically see one tail pipe sootier than the other. That's usually the tell-tale sign, especially if it's the bank 2 tail pipe that is dirtier, as bank 2 is always the side to score first.

 

 

Thanks Charles! Appreciate the insight and clarification about what to listen for and why. Hopefully none of us experience this and its always good to be well informed just in case.

 

Interesting info, thanks for the reply Charles. My C4 has a tick at cold idle that disappears when warm so I assume it's lifters, but I'm still so intrigued about what's going on in those cylinders. I think I'll drop the pan at the next oil change and snake a camera in there.