Where to begin... Recently I have replaced the clutch, flywheel, rear main seal, clutch fork, and input shaft seal. All went well and now I'm having oil consumption problems. ( note: Also I had done an oil change while I had the car torn apart). since then I have topped the mini off very frequently and it's getting to the point where within 100-200 miles it's at the minimum level. I thought that maybe the rear main seal was leaking but I pulled the slave cylinder off and all was dry on the inside. Next, I decided that I'll pull the spark plugs to look for any oil leakage. There I found some. I'll post pictures below. As you can see there was oil inside the spark plug hole and I'm thinking maybe a bad valve cover? Could there be this much leakage through the valve cover? I have replaced the oil filter gasket so I know that's not it. No visible leaks.

 

Also could it be a bad piston ring?

 

to check for rings, do a dry compression and then a wet compression and see the difference. The leak from the valve cover isnt that significant, but you can replace the gasket to eliminate that. did you check the PCV?

 

Well oil can only go to a handful of places. If it is not blowing blue smoke, it's not really burning more than it should be through the thirsty PCV system + CEL would be on and if it's not leaking on your garage floor then maybe look for other variables that may have changed...

If after 150 miles you are losing a quart of oil, it should be pretty obvious as to where it is going. That's a serious leak or burn.

Fill it to the top, leave it sit for a day or two, if it's low, it's definitely leaking somewhere.

The only other thing I can think of would be checking the oil level on an incline which would produce a bad reading, or simply not reading the dipstick correctly, but I doubt that is it since you checked your oil regularly before.

 

I will do a dry and wet compression test and let you guys know. I talked to a local shop that I trust and they said it could possibly be a clogged breather on the valve cover which apparently burns more oil. Still can't believe that something like that is burning that much oil that fast.

 

Update: did a dry compression test and all were at about 100psi. Tested the first one and it came to 88 psi and then tested again and went to 100. Just to be sure I put a tablespoon of oil in all cylinders and tested again. Cylinder 1 - about 30-100 psi kept jumping. cylinder 2 - 120psi. Cylinder 3 was 30-100psi. Cylinder 4 was 120 psi. How do I know if this is valve seals or pistons?

 

Recently was sitting in a parking lot and letting the car idle when the oil pressure light came on. At the time I immediately turned the car off and checked the oil. Oil was completely full. Is this a sign of the engine failing due to possibly bad pistons or valves?

 

So with bad pistons/rings you will notice a lot of oil burn happening. It would set off the check engine light for increased emissions as well as you would be able to see a lot of blue smoke from the exhaust.

With low oil pressure, check your oil filter. My friend had a GTI that had an oil change, then started to have the oil pressure light come on. Sometimes, especially with canister style filters, they can be damaged during install by accident and restrict flow. That would be the first place to check.

Have you lost any oil since the last time you checked? I feel like min level after 150 miles may have been user error. That's extreme to lose 1 quart after such little milage.

I would recheck those compression ratings. If they hit 100+psi then about 30psi, I would go with the higher number being the more accurate one. That would be such a massive loss in performance to be at 30psi that you would be so down on power.

Let me know what you think!

 

Thanks for the reply. This morning I drained the oil which is only 1,000 miles into its life and took the filter out and inspected it. All looked good and I put the same oil in the car. I did in fact mix oil brands (Mobil 1 and Castrol) same weight oil 5w-30. I doubt this is the problem but maybe it is. I've heard that Mobil 1 runs a bit thin but maybe that's just a he said she said type thing. Maybe this was the reason for excessive oil? I usually run castrol until now. Thinking of switching to luiqi- molly oil. Let me know what you think. Currently not driving the car due to the oil problem

 

If you have a cylinder varying between 30 and 100 PSI on test, that cylinder has a problem. I'd suggest having someone pull the plug and scope it. Might be a sticking valve as well, providing intermittent valve seat seal.

Might be a sticking piston ring or something similar, in which case you could try old remedies like soaking the cylinder overnight by pouring in a few spoons of penetrating oil, then turning it over to expel the oil, starting it up, changing the oil, and see if you freed up the ring.

But chances are that you won't hurt it by driving it, as long as you keep feeding it oil. Look for blue smoke - if you see that, the engine is burning it.

You should also check your radiator and make sure there's no oil in the coolant. if so, you probably have a blown head gasket.