1999 Toyota Corona burning through oil in a week

Question

I have a 1999 Toyota Corona with a D4 engine. The engine is giving me trouble and seems to be burning all the oil. It burnt through in about a week (after topping it up completely), and I say burn because there are no leaks.

Its completely useless at the moment and it blew out a whole lot of smoke as I was driving home, before I realized what was happening.

A mechanic took a look and he says its an old engine and it must just be consuming it and that there might be an issue with the transmission? considering the smoke? (not entirely sure).

The thing is that, this car has been giving me trouble from the get go, and this is the 2nd engine on it. The previous one blew out on me for no apparent reason (had done 115k kms) and the one on there now had supposedly done 123k kms.

Any ideas as to what could be wrong? I dont know much about cars but could it just be worn rings around the piston heads?

Not a clue, any speculations would be appreciated.

Thanks

Answer 1

COULD be worn rings, COULD be bad valve stem seals, COULD be blown head gasket. They all require removing the head, which is easier to do if the engine's sitting on the shop floor. Rings require that the engine be pulled all the way apart.

Did your mechanic run a compression test? That'll tell more about this problem than anything else will. Worn rings/cylinders will give you low compression, worn valve stem seals will not. Head gasket might or might not change the compression. At 123 kms, your motor should still have very good compression.

Answer 2

A compression test is part and parcel of this sort of complaint. But dont forget the good old cylinder leakage test. This will pin point areas a lone compression test wil not do. There are cases of this sort of high oil consumption, and in a lot of these cases using a cheaper oil of the wrong viscosity and grade leads to the piston rings becoming gummed up and jammed in their grooves by blow by gases and being unable to perform their job.