This is all your sabotage(?)

September 18, 2006 9:05 AM

Help me solve a 13-year-old mystery involving two cuts in my car's high pressure fuel line and an oil reservoir cap that was removed from its mount.

One evening in 1993, my then-girlfriend and I took a drive from Montgomery County, Maryland, just across the border into West Virginia. We were headed to her parents' cabin in the woods. Shortly before we arrived, I stopped in at a convenience store to pick up some snacks and drinks.

As I pulled into the parking lot, I noticed smoke billowing out from under my car's hood. Alarmed, I parked, opened the hood, and quickly determined that the oil reservoir cap was lying in the engine compartment, off of its seat, and the entire compartment was covered in smoking oil. I topped up my oil with several quarts and replaced the cap, perplexed. It was too late to find a garage. We had driven an hour and a half without a fire starting, so I decided to drive the few remaining miles to the cabin and take the car to a garage the next day.

The next morning, on the way to the garage, we smelled a strong gasoline odor. In the garage's parking lot, I opened the hood (with the car still running), and saw that two steady streams of gasoline were spraying from a small hose directly onto my engine. I shut the engine off immediately and gave my keys to the mechanic.

It turns out that, in addition to my oil reservoir having been left wide open, there were two precise cuts in my high pressure fuel line, far away from any moving engine parts. The cuts looked like what you'd get from a hacksaw, and were just deep enough to reach through the insulation and into the hard plastic material in the center of the hose. They were not cracks, and the rest of the line was completely intact. The mechanic cut out the damaged 3 inches of the fuel line, repaired the rest, and gave me the part of the line that he'd removed. He told me he'd never seen anything like it, and that it looked like sabotage to him (especially in conjunction with the removed oil cap).

Has anyone ever heard of anything like this? What is the likelihood that we were (almost) victims of sabotage? Any other possibilities that I may have overlooked? How lucky am I that the engine compartment didn't burst into flames while flying down 270 at 80miles an hour fo ran hour and a hlaf? I talked to the police about the matter, but they weren't interested in following up on it - not enough evidence.

The auto was a Mercedes 380 SEL (1982). It had a lot of miles on it, but was in mechanically good condition. Any ideas?

posted by syzygy to Travel & Transportation (23 answers total)

obviously the work of itinerant polar bears. can't trust 'em, ever.

more likely it that two unlikely coincidences occurred in temporal proximity to one another.
posted by casconed at 9:51 AM on September 18, 2006

"IS, that", natch
posted by casconed at 9:52 AM on September 18, 2006

This reminds me a lot of this horrible case in Ontario - unsolved until just last year. It hit us in London all pretty hard. Sabotage is definitely a possibility.
posted by Flashman at 10:11 AM on September 18, 2006

"just deep enough to reach through the insulation and into the hard plastic material in the center of the hose."

Someone could probably argue that, by some strange sequence of events, thermodynamic effects together with some sort of stress on the material could cause this to happen, but I don't buy it. Occam's razor and such.

Is there any reason to believe that someone would have it out for you? Angry at your girlfriend?
posted by owenkun at 11:11 AM on September 18, 2006

Er, I meant to imply the possibility that someone else was angry at your girlfriend.
posted by owenkun at 11:13 AM on September 18, 2006

Response by poster: owenkum - There was a strange bartender at the restaurant where she worked. He tried unsuccessfully to get her into the sack that whole summer (blatant harrassment). He really didn't like me, either. I overheard him boasting about having family ties to the mafia once (maybe harmless bluster).

The afternoon before we took our drive, I left the car parked close to her workplace while I did some shopping at a nearby mall.

I guess I'd like to know if anyone's ever heard of someone sabotaging an auto like this, or if there could be another good explanation for the cuts on the fuel line. I was pretty amazed that we hadn't gone up in a fireball that evening´.
posted by syzygy at 11:39 AM on September 18, 2006

From the flash point Wikipedia article:

Petrol (gasoline) is designed for use in an engine which is driven by a spark. The fuel should be premixed with air within its flammable limits and heated above its flash point, then ignited by the spark plug. The fuel should not preignite in the hot engine. Therefore, gasoline is required to have a low flash point and a high autoignition temperature.

I know the ignition temperature of gasoline is ~450 to 500 degrees Fahrenheit. I'd imagine that the engine compartment just wasn't hot enough to cause it to ignite. In fact, it's like that by design.
posted by owenkun at 12:00 PM on September 18, 2006

It's pretty easy to get distracted and leave an oil filler cap off, I drove 400 kilometres from Kamloops to Victoria with one sitting on the air cleaner once.

"The cuts looked like what you'd get from a hacksaw, and were just deep enough to reach through the insulation and into the hard plastic material in the center of the hose."

A hack saw is a really unweildly item to use under a hood. Is it possible it was cut with a serrated knife?

Was your hood openable without having access to the passenger compartment? It's fairly difficult to actuate the latch without damaging the cable from the outside of most cars.
posted by Mitheral at 12:04 PM on September 18, 2006

Response by poster: owenkum: Interesting. So cutting the fuel line is probably not a particularly reliable method of injuring someone.

Mitheral: It could have been done with a serrated knife, or perhaps one of the saws on a larger Swiss Army Knife. The hood was not normally openable from outside, except that it was easy to close the hood halfway without noticing it. When that happened, the hood would stay closed while driving, but would be openable without having to get into the passenger compartment.
posted by syzygy at 12:12 PM on September 18, 2006

Here's my theory: You, or someone who had recently opened the oil cap, left it off. Hot oil splashed around the engine. Some of it landed on the fuel line. Some fuel lines are braided hose wrapped in a softer rubber that crumbles when the outer surface is exposed to gasoline or other petroleum product (my '88 Volkswagen, for instance, was like this, I chalked it up to European ingenuity). The oil ate through the fuel line.

My other theory: The oil cap vibrated loose and fell off. It hit the fan, which sent it ricocheting around the engine compartment. During this journey, it hit the fuel line and cut it.
posted by M.C. Lo-Carb! at 1:43 PM on September 18, 2006

Your theory requires the bartender to have come across your car nearby his work, prepared with a hacksaw to sabotage it, on the same day that you neglected to close the hood fully. Seems like a lot to hang on coincidence.

Even if all that happened, why would he remove the oil cap? That just creates smoke, which warns you that there is a problem.

IMHO, myth busted.
posted by InfidelZombie at 2:03 PM on September 18, 2006

Response by poster: Lo-Carb: Two interesting theories, but I'm not too convinced. First, the oil cap was still in the compartment, near the reservior fill hole, on the opposite side of the engine from the fuel line. The two breaches in the line looked like cuts more than failure due to exposure to oil - they were too clean, and too localized. Also, no woven material on this fuel line - it had a somewhat soft rubber outer coating with a harder internal plastic layer.

Infidel: For clarification, I parked near my girlfriend's workplace several times per week that summer, as I worked in the same mall (crap summer jobs for college kids). I'm leaning toward "weird coincidence" as well, but I'm still not convinced.
posted by syzygy at 2:23 PM on September 18, 2006

Indeed, engine oil somehow eating a hole in the fuel line seems very unlikely.

Gaining access to the engine compartment would likely be easy. Virtually all the cars on the road back then could easily be opened with a "slim jim" or the like.

I do like the "oil cap vibrated loose and fell off. It hit the fan" theory, since it explains both the oil cap being off (yet still in the car) and the fuel line cut. If it were sabotage, the only reason I can think why they'd remove the oil cap is to pour something toxic in, in which case they'd replace it; or they just wanted to annoy you, in which case they'd throw it away.
posted by sfenders at 3:39 PM on September 18, 2006

That sounds very much like a deliberate plan. Gas line pierced but not cut, to allow driving time to heat the engine. Oil cap loosened so it will fall off, spraying stickier engine oil about to help spread the fire after the more flammable gasoline ignites.
Normally oil will not ignite when dripped on an engine block, but if the exhaust manifold gets hot enough oil dripping on it (from leaky rocker cover gaskets, for example) can ignite. This happened to me on highway 401 in Ontario - the result was not be a fireball (too windy and open in there to build up a concentration of fumes) but a drop in engine power as the flame ate through spark plug wires, until the engine stalled and I pulled over just in time to see flames licking up the windshield.

It would be interesting to do some detective work and see if that creep has developed a criminal record by now.
posted by CynicalKnight at 8:06 PM on September 18, 2006

Rats and other rodent-like creatures, like marmots, will sometimes climb into a car's engine and gnaw on hoses. These animals have sharp teeth and could conceiveably snip right through a hose, making it appear to be done with a hacksaw. The oil cap happening at the same time you first noticed the damage could've been a simple coincidence.
posted by frogan at 10:06 PM on September 18, 2006

Here's my theories:

Gas cap - since it was near where it would have been taken off, sounds entirely likely that it could have been accidentally left off sometime in the past. Not an uncommon occurrence at all.

Fuel line - you're parked at a cabin, you say? With, for example, squirrels and rats and other sharpy toothed annoying creatures who build nests out of soft things like insulation? And you didn't notice the gasoline smell and spraying gasoline the day before? Sounds like some creature got into your engine compartment overnight and chewed off some insulation, but then decided it was bad juju when it got sprayed with gas from the fuel line. If you were driving for an hour and a half at 80 mph with a cut fuel line, methinks you would have:
a) smelled the gasoline before the next day
b) noticed that your gas mileage was extremely poor

Since we have no way to say for sure what happened here (barring a time machine) I think it's all just going to be guesswork anyway. If you had kept the fuel line chunk all these years, we could have examined pictures of it to see if it really DID look like a hacksaw, or if it looked more like teeth marks.
posted by antifuse at 3:10 AM on September 19, 2006

Response by poster: sfenders: on the oil cap, I was thinking along the lines of CynicalKnight's suggestion. Like the gasoline was to serve as a quick accelerant and the oil coating my entire engine compartment (including the firewall) was the slow burner.

CynicalKnight: That's how the whole things struck me, honestly. I'll see if I can find anything out about the bartender - hadn't thought of doing that.

frogan: The examples of that kind of damage that I have seen before weren't as clean as these cuts, but it's still a possibility.

I was hoping to hear if anyone was familiar with this sort of technique as a common method of sabotage. So far, no dice. Perhaps it was simply a coincidence.
posted by syzygy at 3:28 AM on September 19, 2006

Response by poster: antifuse: I was parked at an urban mall before I left for the cabin. I noticed the smoking on the way to the cabin, so the damage either happened in an urban setting or on the way to the cabin. I do still have the fuel line, but it's in Texas, and I live in Austria now, so I don't know how easy it would be to get a photo. I'll see what I can do on that front. Unfortunately, the time machine that I've ordered won't be delivered until a couple of years ago.
posted by syzygy at 3:31 AM on September 19, 2006

bear in mind this is an old Mercedes, so it's diesel... which has a lower flashpoint (> 62°C) and autoignition (210°) than regular petrol
posted by trinarian at 4:22 AM on September 19, 2006

You were parked at an urban mall before you left for the cabin, but you didn't notice the fuel smell at all on the way up to the cabin, which I contend to be a bit strange, since you smelled it immediately on the way to the garage the next day. After being parked at the cabin overnight. I still hold to my original sharp-toothed creature theory :)
posted by antifuse at 4:29 AM on September 19, 2006

One more reason it seems a good possibility that the oil filler cap did the damage is that there were two cuts in the gas line, just about the right distance apart.

I think a hypothetical saboteur mad enough to try this complicated and unreliable method of setting fire to a car, yet precise enough to make exactly the right depth of cut, would've been more likely to cut the line in one or in a dozen places.
posted by sfenders at 5:33 AM on September 19, 2006

Response by poster: trinarian: The 380 SEL was a gasoline model.

antifuse: On the drive out to WV, it was evening/nighttime. I was driving fast, and it was cool, so the windows were closed. When I stopped at the convenience store that evening, I mostly noticed the smoking oil smell. The next morning, on the way to the garage, it was sunny and warm, and I was driving much slower, with windows and sunroof open. But you still might be right.

sfenders: I have to admit, I like the oil filler cap theory, as it would explain both problems, but the shape of things under the hood (where the oil filler was located, where the high pressure fuel line was located, the part of the line that was cut, and where I found the oil cap lying), make the theory seem a little less plausible. Can't discount it completely, though.
posted by syzygy at 9:12 AM on September 19, 2006

I go for the sabotage theory, and with a sophisticated saboteur, to boot.

The point of leaving the oil cap off is to cause the engine to lose its oil, thereby allowing the engine to overheat enough to catch the gas on fire. Without that, the chance of an engine fire are not very high, given the flashpoint of gasoline.

I would also say that the two cuts in the gas line could have been intentional. The function of the second cut would be to distribute gas more widely, or to act like the aerator on your kitchen faucet (which has small holes in front of the main opening to suck in air that mixes with the water stream) and suck in air which would mix with the gas and thereby satisfy the other precondition, besides temperature, for a fire. Of course, that isn't what you saw when you opened the hood; a stream of gas was coming out of each hole.
posted by jamjam at 5:35 PM on September 24, 2006