I think I killed my car.

March 3, 2007 8:45 PM

CarOilFilter: Oh, dear lord. I put oil in my car tonight, and thought everything was fine until ...

I got home and realized I had left the cap off. There was oil everywhere, pouring in dark brown streams out from under the hood. I noticed a bit of an oily smell while I was driving, but just figured I had spilled a bit as I was pouring and didn't think much of it.

Anyway, I put the cap back on, cleaned the mess up as much as I could, and now I need to know what to do next. Have I totally fucked up my car? Do I need to take it to a mechanic ASAP? I'm worried about the hoses and various things under the hood about which I know very little. I'm worried about fires and smoke and overheating and bad things about which I also know very little.

Has this ever happened to any of you, and do you have any advice on what I need to do in the morning?

posted by brina to travel & transportation (20 comments total)

Clean off as much as you can again. Check the oil level when the car is cold, and top off to full. This time, remember the cap.

It will keep smelling for a while, but the odds are against anything being broken unless you were running your engine with too little oil, which you'll know if your dipstick is dry.

On the other hand, if "pouring" isn't an exaggeration, I wonder if something else is amiss.
posted by Kwantsar at 8:51 PM on March 3, 2007

The smell was probably oil smoking and burning from touching the hot parts of the engine.

I guess I would try to clean everything up well, particularly oil that might have gotten on the hot parts of the engine (exhaust manifold, etc.). Might even be worth employing some engine degreaser, although that may be overkill.

Anyway, then I'd just refill the oil to the correct level as per the dipstick, and put a clean sheet of cardboard under it, and see if it leaks. If no leaks, then take it out and drive it around, and see if any lights go on, and then park it back on the cardboard and see if it leaks when warm. If not, I'd say you're good to go. But if at any point in the procedure it starts leaking oil again, then I'd consider whether there wasn't something else wrong (oil filter not seated, maybe? drain plug? etc.).
posted by Kadin2048 at 8:57 PM on March 3, 2007

If you've already reached this point, you are probably fine. my mom was always forgetting the oil cap. she never lost it. it was always sitting on the engine where she left it. she only once set the car on fire doing that. one minute, we're driving and things are dandy, the next the hood is smoking. we pull over, she pops the hood, and flames shoot out. i wish i could say it was the last time she did that, but alas, if that were the case we wouldn't be referencing my mother.
posted by nadawi at 9:02 PM on March 3, 2007 [3 favorites]

Most professional hand carwashes have a steam cleaner for engines (probably will set you back $20). Have that done to avoid any excess smoking. If you didn't hear any kind of chatter coming from your engine (ie. valves banging against cylinder heads or crankcase) or any other strange noise then you probably don't have to worry about any engine damage.

Also, what others said.
posted by Burhanistan at 9:27 PM on March 3, 2007

you're fine, i did this last summer and nothing bad happened. just top it off!
posted by soma lkzx at 9:31 PM on March 3, 2007

Everything is fine. You let oil spill out onto hot parts which makes a big mess. Do you really care if the car is dirty under the hood? If not, just make sure you have enough oil. If so, have it steam cleaned.
posted by caddis at 9:34 PM on March 3, 2007

Thanks, everyone. I couldn't afford to have my car die on me right now.
posted by brina at 9:39 PM on March 3, 2007

No big deal - your car would have let you know if it was. Top the oil off, go to a DIY carwash and clean the engine bay thoroughly with the engine running.
posted by notsnot at 9:39 PM on March 3, 2007

I drove around for three days once trying to figure out why my engine sounded different. Bit of a mess but no big deal.
posted by DieHipsterDie at 9:54 PM on March 3, 2007

The oil is actually pretty good protection against the elements, I wouldn't bother having it cleaned off. As others said, your car is very likely to be just fine. Make sure you get enough oil back in there and you're good to go.
posted by knave at 10:52 PM on March 3, 2007

I'm a little less sanguine about this than other posters, for reasons I'll cover in a minute. But I'd say it would be easier to give a good answer to this question if a) we knew the year, make and model of the car, and the type of engine, and b) we knew approximately how much oil was sprayed out of the filler cap, (which you would read off the dipstick before refilling the crankcase) and c) we had some pictures of the mess, if it is very bad. If you're really concerned, brina, post back with those basics.

Otherwise, if I were you, I'd have a good look, in daylight, at the belts that drive your engine accessories (power steering pump, alternator, air conditioner compressor). You may have a single cogged serpentine belt, or you may have a combination of a serpentine belt and one or more V belts, or you may just have one or more V belts, depending on how the manufacturer designed the car. Regardless, belts are not supposed to be oily, and if you did get a lot of oil on them, you can expect a shorter life, and maybe squealing noises, or in the worst case, not having enough power delivered to your air conditioner compressor, alternator or power steering pump to operate these accessories normally. So, I'd have a good look at the belts, and with the engine off, run my fingers over the belts and pulleys to see if they were slippery. If you got a lot of oil on them, you may need to replace the belts.

I'd also suggest you examine your battery carefully. Oil spray will attract and bind various kinds of dust, and if you get a thick coating of metallic dust on your battery case between the terminals, it can produce a slow discharge leakage path, that can drain the battery over the course of a few days, if the car isn't run. This is more a problem with older cars, say from the early or mid '90s, because they generally had older post style batteries, but a battery should be kept clean. You can wipe the exterior of your battery clean with paper towels, and you can mop up excess oil you see on fender wells, valve covers, relay boxes, fuse boxes, and other engine accessories with paper towels, too. You'll hurt nothing, on a cold engine, by wiping it down with a paper towel (but you won't necessarily get all all the oil removed from a metal or plastic surface so easily). Also with respect to electrical components, if you really soaked older style ignition components like a distributor, or spark plug wires, particularly a non-metallic conductor set with lot of miles on it, that may have some insulation cracks, you could develop an ignition mis-fire shortly, or worse, have a site from which sparks or fire could develop. So, you should visually check all the spark plug wires thoroughly, but this is more important for some makes and models than others.

If you got a lot of oil on the radiator or automatic transmission cooler at the front of the engine compartment, you could also quickly see a buildup of greasy dirt on these components. That inhibits the transfer of heat to the atmosphere. Again, it's a question of degree. Most cars have some excess cooling capacity, but if you get a thick coating of crud on the radiator of a cooling system that hasn't been maintained, it can be the thing that tips the scales.

And obviously, if you pumped enough oil out that a pool of several ounces collected in a spark plug well, or near an exhaust manifold, you could have an under hood fire. It's a question of degree and amount, but also a question of design, as some engines are far more prone to this than others. You have to look carefully, inch by inch, at the intake manifold, the engine head, and the exhaust manifolds to find and remove any small pools of oil.

Finally, I disagree with knave and others, in that if you drive around with a dirty engine all the time, it's a lot harder to notice small problems that begin as minor fluid leaks, because they are hidden by all the dirt. You keep an engine clean, to be able to see small problems, while they are still easy and cheap to fix.

So, I'd make a prudent inspection under the hood, in daylight, if I were you, before dismissing the situation from mind, on the strength of anecdotes from random strangers on an Internet forum, who don't have any of the facts that would be needed to make a good recommendation. It's likely that you've done no permanent harm, but until you confirm that you haven't, for real, you would be better off by far, in my estimation, resolving to check things out. Particularly if you cannot afford major headaches in the near future.
posted by paulsc at 11:40 PM on March 3, 2007 [1 favorite]

The oil is actually pretty good protection against the elements, I wouldn't bother having it cleaned off.

That's really some very bad advice.

Motor oil + heat = degraded belts and hoses. Lower lifespan on these components means leaks and system failures that could be very costly down the line. Oil also is a dirt magnet: once the engine bay starts getting dirty, it'll just keep getting dirtier exponentially. All that extra gunk (road salt, sand, water, etc.) inside the hard-to-reach areas of the engine bay eventually leads to rust, which leads to car-death.

In other words, clean your fucking car.

It's actually not very difficult to do it yourself, but as mentioned above, you can take it to just about anywhere and pay someone to do it for you. FYI, Gunk Engine Brite is the bees knees. Just cover up the electrical connections (including spark plugs), spray that stuff all over the place, let it sit for a while, then gently spray down the engine bay and wash it off. Engine clean. To be on the safe side, wait a few hours for everything to dry out (do it on a nice sunny day if possible, or get a hair dryer if you live in cooler climates).
posted by Civil_Disobedient at 12:48 AM on March 4, 2007 [1 favorite]

1) you lost some oil from your engine. It most likely looks worse than it is because the rad fan basicaly atomizes the oil as it comes up out of the open filler there by spreading it around really good.

2) Unless your oil light came on you probably didn't damage any internal components. Top the crankcase up (I'd bet it takes less than a litre). You used to be able to empty some engines in short order because the rocker oilers would fling oil right out of the filler hole if the cap was off. Almost everything made in the last thirty/forty years incorporates a baffle in the valve cover if that would be a problem exactly because people tend to leave the cap off.

3) As paulsc says there are many reasons for keeping an engine bay clean. That goes double for removing a coat of oil. So take the car down to the U-do car wash and give the engine compartment a good wash. I never leave the engine running, about the only thing that'll be messed up by the water is a distributor or computer so just avoid spraying those items. And don't direct the water spray into the intake.

3a) Also clean the windshield really well, you probably got a fine mist of oil on it which will streak when you apply the wipers. You probably don't have much oil on your rad because the oil leak was down stream from the air going over it but it never hurts to give it a good cleaning anyways just to rid it of road dirt.

I personally wouldn't be very concerned about oil contamination on your belts. Modern belts are pretty oil resistant and unlike a leak that drips oil onto a belt your belts were mostly exposed while the car was running. The belts in motion would do a pretty good job of flinging the oil away and the car wash should take care of any residue.
posted by Mitheral at 12:54 AM on March 4, 2007

I seriously make this mistake every other month. As everyone else is saying, as long as you replenish the oil, there's no big worry here.

Also keep in mind that you can get your engine detailed (for about $40) at a professional car wash joint. I personally wouldn't bother, but if you are really concerned about the smell and too busy/lazy to use Gunk.
posted by nasp at 5:50 AM on March 4, 2007

If you do decide to clean it yourself please remember not to hose down a hot engine. You might crack something. If it is too hot to touch it is too hot to hose.
posted by caddis at 7:50 AM on March 4, 2007

And if it were my car, I'd get the oil changed as well, rather than just topping it up. But this is mainly because the last time one of my cars had an oil filler cap left off, we were on the Gibb River Road, and the engine filled up with bulldust and got chewed to pieces. So I'm probably oversensitive.
posted by flabdablet at 3:34 PM on March 4, 2007

I made this mistake once, and I hate to say it, but the car was never the same again. We drove for almost a whole tank (road trip) and ended up running with too little oil for too long. Ended up needing a ring job, but sold the car 'cause I couldn't afford it. Bad stuff.
posted by johngumbo at 4:22 PM on March 4, 2007

Just to add to your confusion you can put me in with the "do not clean your engine"camp. Obviously opinions differ on the matter. Were I you I would use some paper towels to remove all the remaining oil but I am personally firmly opposed to engine cleaners and water in the engine compartment. Mop up everything best you can.

I think the risks of damage from running with little oil - if the loss was as severe as you describe - is more likely than issues with oil all over the compartment, however it's not anything you can do anything about beyond refilling the oil to the proper level.
posted by phearlez at 12:36 PM on March 5, 2007

Just to back up what I said (since I got torn into), I need more than two hands to count the number of times I've heard, "I just washed/cleaned my engine and now it won't start! Help!"
posted by knave at 1:19 PM on March 6, 2007

When you clean your engine, you can avoid the "now it won't start!" business if you just resist the temptation to aim a jet of hot high-pressure super-water into anything electrical.
posted by flabdablet at 3:55 AM on March 7, 2007