I have a 2001 Hyundai XG 300 that’s more or less my beater/daily driver. Its in reasonable shape at 140k miles but it does burn a bit of oil, especially upon throttle from a dead stop and it seems to start spewing smoke if I’m at idle for long periods of time like when I’m in traffic.
Anyway, I’d like to keep this car going for quite a while if possible without really investing any major money into it. So: do ANY of the oil additives on the market that claim to “help” or in any way reduce oil consumption/burning actually work?
I’d love to hear from our resident car gurus if they know of a product that can at least slow down how much oil I am burning. I can’t pretend I’m playing Spy Hunter and throwing down the smokescreen forever.
You have engine wear with worn/stuck oil control rings and or leaky valve stem seals. The oil smoke while idling pretty well suggests this. I once owned a 76 Vega and later an 83’ Malibu that I drove for 22 years. Both of these vehicles had leaky valve seals that caused smoking badly on startup and while idling for periods. While I am not generally a fan of oil additives, I have always been a fan of STP oil products. This excessive smoking almost completely abated when I used STP in the engines. The overall oil consumption was not reduced so much, but this annoying smoke problem was. It costs very little to try this and it won’t hurt anything.
Oil consumption is not a major problem in itself. The vehicle can run almost forever as long as you keep the oil level up. Don’t skimp on topping it off and never depend on gauges or lights to tell you to add oil. Check the stick yourself and top off. All that oil usage is bound to cause your converter to go bad if not already. And the oxygen sensors are probably already giving you an orange light on the dash. You can’t afford to fix all these things without doing everything including the engine so I advise limping along and getting the most out of it without spending big cash. If you can put your own oxygen sensor in yourself for $30 it might last 20,000 miles or so, just a guess. Don’t go overboard.
no, not really. it might help a little bit by increasing the viscosity of your oil, but you could get a similar effect with just using a higher viscosity oil in the first place.
The other thing those oil treatments usually do is add a bunch of ZDDP, which was traditionally put in motor oils as an anti-wear additive. ZDDP content has been reduced significantly in newer API specs because it can harm the catalytic converter.
Thanks, I might try STP, although the internet seems to be pushing me towards a product called Alemite, coupled with straight 40 weight oil. Apparently the Alemite will expand the seals on the rings (??) over a short period of time and the more viscous oil is required so that it doesn’t “blow through” the seal “wall” the Alemite is allegedly creating. Color me skeptical. I do check the oil religiously and add whenever necessary, and no…no check engine lights.
Yeah, I read about that (ZDDP is a type of zinc, right?). Apparently it causes deposit buildup.
I’m not looking for a miracle cure but anything to reduce/stop the smoke emission would be great. I can deal with adding oil every now and then. The smoke is kinda embarrassing.
In some rare cases where the oil control rings are stuck due to varnish build-up, certain additives could help unstick them and reduce the oil burning. Of course, those additives are basically solvents and don’t help any with actual lubrication. If the problem is worn rings, which is more common, additives aren’t going to do much, if any, good.
I agree that it won’t hurt to try a can of STP, though of course it won’t necessarily help. I also agree that so long as the oil level is maintained, the engine may run okay for quite a while. If it gets to the point where spark plugs are being fouled rather quickly, then it becomes a less manageable problem, but cross that bridge when you come to it.
ETA: I worry about using SAE 40 oil. It’s not going to flow well in a cold engine (as in has sat for several hours, regardless of the outside temp) and could hasten the engine’s ultimate demise.
Using oil additives are generally not a recommended practice by both engine makers and lubricant makers. In both cases it’s because the additive adds unknown chemistry.
Where I work, we frequently run R&D engines hundreds of thousands of miles of simulated miles, and the oil is rarely (if ever) changed. (We call it highly accelerated lift testing, or “HALT.”) Even at that, it’s rare to see smoke, and if there is, it’s usually from piston rings jammed with carbon. Sometimes it’s from worn valve guides that allow excessive radial play in the valve, which eats up the valve seal. Occasionally it’s other things, but these are the main two items, with the jammed rings being the culprit most of the time. Of course, there are numerous other factors, but I can’t disclose most of it.
A way to clean up the jammed ring issue is by use of a high-detergent non-synthetic motor oil; usually these are intended for diesel engines due to the amount of soot in diesel fuel. Mobil Delvac, Shell Rotella, etc. Downside is these are generally 15W-40 oils, where most of your modern car engines prefer 5W-30. Running the 15W-40 shouldn’t hurt anything, but your fuel economy will take a hit.
If the valve guides/valve seals are what’s causing the smoke, you’re pretty much out of luck as far as fixing it with an oil change.
When I bought the car the plugs were utterly fouled. I had a mechanic check it out and he changed the plugs and wires and replaced the tube seals which stopped the plug fouling and got the check engine light to go away. I also had to replace the air plenum gasket as well. Other than that, two new tires, front wheel bearings and calipers, pads and rotors all around, the car has set me back about $4k total including the purchase price of the car. It runs smoothly, still has decent power (although I don’t really push it, that’s what the Mustang GT is for!) and my only complaint other than the smoking issue/oil consumption is worn suspension components leading to lots of body roll and it needs a new radio.
Alemite CD2 (now owned by Turtlewax) is just a viscosity modifier. nothing special.
The piston rings are the seals, and they’re metal. An oil additive can’t expand them. However, the piston rings work in concert with the film of oil on the cylinder wall to provide the sealing (dry rings don’t seal.) If you’re dealing with worn rings or tapered cylinders, increasing the viscosity might help it seal a little better. but don’t expect miracles. If the valve seals and/or guides are worn, again a viscosity increase might help a little bit.
ETA: I’m pretty staunchly anti-additive for new/new-ish cars, but when you’re limping along an old worn-out engine, it doesn’t hurt to try them
It’s the stuff in the can. It pretty much cured a quart per 500 miles consumption problem I had with an old Chevette. It’s the only additive Click and Clack say will work sometimes.
One of the things that can fool you here is the “add-a-quart” syndrome. Because the car uses so much oil, you keep adding and never change it all, so you end up with old dirty oil that burns 2 or 3 times as fast as new oil. Going to a heavier oil can’t really hurt, as you’re half a step from tearing the engine down anyway. So maybe it rattles for 20 seconds or so when you start up…so what? There is a remote chance - if you have a piston oil ring(s) carbon-stuck in their grooves - that adding a quart of trans fluid to the oil for 2 weeks will break them loose. If the guides and seals are gone, there’s no hope but heavier oil (FYI you can buy up to 70W racing oil so 10/40 is nothing special) or a rebuild. If you do a compression test and then squirt some oil down the holes and do a second test…and the numbers went UP, then you have bad rings. If the numbers DID NOT go up, then it’s the valves making the trouble and the appropriate person could maybe change the valve seals without taking the motor apart and stop the smoke.
Before making a science project out of this, go on a forum for your car/model and make sure you don’t have a plugged EGR valve or flametrap or whatever your car has. It could be that simple.
Hah…I’d love to do that but I don’t like to drive the Stang in the rain (it gets dirty, then I have to give it a full body rubdown…again), I won’t drive it in the snow and I want to keep miles off of it. Plus I often have my two growing sons (10 and 6) with me and the Mustang isn’t very practical for transporting them as the “back seat” in the Mustang is only for hamsters. And then there’s the cost of gas…the Mustang gets like 17-18mpg combined, the Hyundai gets roughly 28.
Plus I own the Hyundai outright and have a note on the Mustang.
So I am keeping the Hyundai, just looking for a possible reduction of my smoke trail without having to spend a bunch of money on the thing. It runs really well. It just uses up oil like a mofo.
Most of the time, worn seals are the issue-an experienced mechanic can determine if the oil burning is due to worn seals or worn rings/scored cylinder walls. It involves checking the compression in each cylinder-then squirting in a bit of engine oil-if the compression comes up, it is worn rings or scored walls. This is a rare condtiion-most of the time, it is the valve seals. Replacing these is pretty cheap-for a 4 cylinder engine , usually $300-$400 (depending how accessable the engine head is).
Now for the fun: sometimes, an old-time mechanic trick will work-but it is a dangerous procedure (add too much and you can destroy the engine). The procedure is to add a few ounces of brake fluid to the sump-the brake fluid will soften the seals and cause them to swell-temporarily stopping the oil burning.
This works…sometimes. If you want to keep the car, i’d go the replacement seals route (if the rings are still good).
it depends on the engine, most frequently like you say oil burning comes via valve seals/guides. On some parent-bore (linerless) diesels like the older Navistar 6.9/7.3, oil consumption is mostly cause by cylinder taper. The blow-by kicks up a mist of oil in the crankcase which gets sucked into the intake and burned. The 6.9 liter Ford I had years ago drank a quart every couple of weeks.