1.8vvti oil consumption

[Jamcal]

Apologies for bringing up this old chestnut but I have a 2004 Corolla Verso which is using about a litre of oil per 500 miles. Its on 11200 miles and I was hoping to hang on to it for a couple more years or another 20,000 or so miles.  The catalytic converter has been outside it's threshold level for the last couple of years but I turn the light off and it gets through MOT's without issues. I try to drive it gingerly without revving too much but it is a bit sluggish on hills. I have read about using thicker oil ( I use Toyota 5W30) and the local Toyota garage reckons it needs new piston rings. Now I'm weighing up options. If I do nothing and just carry on shelling out on oil am I inviting catastrophic failure? Is it worth finding a back street garage to change the piston rings or is this just throwing good money after bad? Should I just accept it's done its job and say goodbye to it? I could do with a bit of advice from people in the know.

[FROSTYBALLS]

Presume it is on 112,000?

[Jamcal]

Yes. Sorry , missed that zero. Bought it when it was on about 60,000. Oil consumption has gone up by at least a third over this time.

[Bernard Foy]

4 minutes ago, Jamcal said:

Yes. Sorry , missed that zero. Bought it when it was on about 60,000. Oil consumption has gone up by at least a third over this time.

Yes I wondered at the mileage when I first read the post. My thoughts are, you have two options one is to put it through the MOT and sell it on, or if the car is really sound and free from rust it is probably worth a new set of rings a good de-coke and the valves ground, you could probably get another five years of motoring out of it. But as we all know as motors get older they do require more maintenance.

[Jamcal]

Thank you for your thoughts. I think the car is basically sound. I had a driveshaft break a few years ago which was down to a corrosion issue but the bodywork looks good. The MOT is coming up so I can get them to give it a good look over then. It has always passed first go with no issues in the past and the advisories are generally minor issues/wear and tear. I would like to hang on to it if the economics stack up so I'll put it through the MOT and get some quotes for the work you suggest. 

[NGRhodes]

These engines were updated later with pistons with larger/more oil return holes which completely eliminates issue, so if you do get the rings replaced and pistons cleaned, ensure someone machines your pistons with more/larger holes (I can't remember which) or the issue will return.

I used to have a 2003 with the same engine, I tried 5w40 (as used by Lotus with the same engine in their Elise to better handle the high  performance usage) instead of 5w30 and it made no difference to oil consumption, mine stayed steady at about 500ml of oil per 1000 miles.

The primary problem with these engines is the oil collects around the rings due to insufficient drainage, burns off and carbon deposits until the return holes clog, rings sticking is a secondary effect.

One countermeasure to reduce the oil temperature at the rings (to prevent oil burn off) was to use 0.5 litres of oil extra, there is an updated dipstick available with 10mm higher markings, this will have no effect if your ring oil return holes are already blocked.

Some people have claimed success with doing an overnight piston soak, note that the issue will return, so repeated use would be needed. Its worth looking out for a piston soak containing PEA, this is a great chemical for softening hard carbon deposits.

[Cyker]

It's a lot of work to properly fix; Some people have luck with Seafoam or Terraclean to stave off the worst of it, but ultimately the revised pistons etc. need to be fitted to properly solve the problem. It really boils down to how much you like the car and whether you want to keep it as a long-termer, or run it into the ground while saving for a replacement!

 

[Jamcal]

Thank you to all for the advice. I guess what I really want is to stave off the worst of the issue and get a bit more usage from the car without having to do major (expensive ) work that wouldn't really stack up economically. I will look into the piston soak idea as well as replacing the rings although I imagine the latter would be costly. As far as running it into the ground, what is the worst that could happen.? Is there a possibility of catastrophic engine failure at speed? At the moment there doesn't seem to be any visual or audible indication of trouble. I can't see any smoke and there are no knocking sounds. The only sign I have is the increasing disappearance of oil.