Hi,

I check the engine oil every week, for about a month, it is a little under the H level. After I planned a long trip to Toronto, a 7-hour 2-way trip, I lost 2 quarts of engine oil. This does not happen on short distances, like 4 trips, lasting 15 minute each. I do not see any leak under the car, do not see any blue smoke coming from the exhaust. What can be happening? Where should I check before I bring it to my mechanic?

Well losing two quarts of oil over a seven hour trip is indicative of something that needs to be taken care of. If you're not leaking oil, it is being consumed somewhere. I'd try and find somebody to follow your car and see if it stinks like hell when it drives. It probably does. Alternatively try and find if it's leaking into something - namely, the coolant. Lift the radiator cap and see if the coolant looks good.

Really though I'd bet it's just burning oil at a good rate, but not quite enough to see smoke. I bet your exhaust smells pretty funky!

What does a regular exhaust smell like? Light smell? For mine, it have a semi-strong smell. It smells like other cars at parking. Anywhere I can check to do-it-myself before going to the mechanic? Also, I drove 500 miles short trips @ 6 miles per trip for 3 weeks, but did not lose any engine oil, but only for long distance.

You may have been losing some on the small trips, but were just not as aware of it...?

In regards to how it smells, when you're behind a car driving you should not be smelling it. If you put your nose up to the exhaust of a car that is fully warmed up (don't do it for too long or you die!) it should smell "warm". That's how I'd describe it. It won't smell pure like air, but it shouldn't have much of a smell to it.

Sometimes in the parking lot at work I smell a nasty ole smell and I know it's one of the cars there after it's parked. Most will give off a tiny odour, or none, but this car (and a car I used to own also did it) evidently give off a nasty burny smell after being driven for a bit.

Another possibility: check for a leak that only shows itself when the engine is on (i.e. oil pressure is up). Years ago, my dad had this happen when a tiny splinter of wood got caught on the oil filter gasket. It leaked with pressure, but as soon as you turned off the car and started looking, it disappeared. Check using a light and perhaps with some light paper or a clean cloth spread out under the engine so you can easily spot such leaks.

Good luck. I hope it's something like this and not a deep, internal flaw in your engine structure.

Another thought (just going stream of ideas here...). Maybe you've got sticky rings, which are allowing excessive oil burning, especially during sustained high speed running, like on a highway trip. If you evidence indicates that this could possibly be your problem, it might be worth trying an Auto-RX cleanup before you tear into your block.

I added up the small trips to about 500-600 miles for the first 3 weeks after the oil change, no leaks at all. The same oil reads a little under the H.

It will only happen when the engine is on and on long distance. I drove for 7 hours, approximately 500 miles, and lost 2 quarts. I just hope it's not anything serious, but 2 quarts for 500 miles is a lot. I read about other sources of engine leak, and requires plenty of labor in removing the engine or even changing the engine. I hope that's not the case. As for checking for pressure leak, I hope it is a small problem there. I will check next week for more "engine on" leaks. As for the smell on the back of the exhaust, it is not strong, but can smell it from standing near it. Smells like burning, but not a lot. But standing next to someone's else car smelled the same. (2 other cars) If it is a pressure problem, how can I really check or replace the seals for the leakage problem?

What is this Auto-RX cleanup? It seems like it matches my description, high speed running. Where are these sticky rings located and how to get this fixed?

I'm talking about the piston rings inside your engine. The lower of the three on each piston is what's known as an "oil control" ring. Its job is to keep the right amount of oil in the right place along the cylinder wall as the piston moves back and forth in the cyl, and critically, it "wipes" excess oil back down the cyl walls so it can drain back to the sump. If just a bit of sticky gunk prevents these rings from moving as they are designed to move, then a lot of oil can move up past them and into the upper cyl where it then gets burned.

Auto-Rx is an engine cleaning product that a lot of folks seem to be pretty pleased with (I have no stake in this product). It is a slow, non-harsh, non-solvent product that should be less risky than the kerosene-based cleaners. Run a google on the name, and you should find all the info you need to order, of you choose to do so.

I checked Auto-RX's website. I believe it takes approximately 9000 miles to "complete" seal the leak. I think that will take a while to believe that it might work. I want to check out the oil control rings that you are talking about. Any idea on how to take it out and place it?

I hope you're not pulling my leg. . . I won't pull yours. You're looking at completely disassembling your engine to get at the rings, one set around each piston, in effect sealing them against the cylinder walls (among other things, like controlling oil). Don't try this at home. Do an Auto-Rx first.

Ouch...I thought I can do this myself. Probably Auto-RX is the best way to go. There's another product I saw on Pep-boys that says "Stop Engine Oil Leak." Think that's good. Costs only $2.50.

I checked the smell from the exhaust today, and it smells almost like nothing. It did smell a little bit or something when I start the car. So I guess it's not burning oil. Drove for 50 miles today for an hour, no loss of oil today...speed -> 50 mph, acceleration -> slow. I will be going on another 5 hour trip in 2 weeks. After that, if engine oil leakage persist, I get a new oil change and do the Auto-RX. Trying to avoid the mechanics as much as possible. Did you ever happen to have the same problem as me?

Anyone else have this problem before?

Anyway, I will be planning to use the Auto-RX when I come back in 2 weeks. I hope it will work well to avoid going to the mechanics. Hope I get good results.

Add-on: The oil on the dipstick is pretty dark-brown.

Thing about oil color is it's hard to use to determine oil quality. Often it will get dark brown after only several hundred miles, but can still be in good condition.

Regarding the oil stop leak stuff I would not bother with it, because oil additives are mroe times than not not worth using (or worse). However, some manufacturers like valvoline have oil they sell with built in stop-leak (valvoline's is called Max Life). Given that these have to adhere to a standard, I would trust them to be safe, whereas with the stop-leak additives you buy you don't know if you're putting in glue or whatever.

How about Auto-RX, recommended?