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Car allergic to vanilla ice cream (2000)

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Re: Car allergic to vanilla ice cream (2000)

#101

Post by [deleted] »

addaon wrote: post #40
bell-cot wrote: post #2

This reminds me of a GM minivan that my youngest brother-in-law drove, back in the '80's. He'd gotten it from his father, who was a career GM automotive engineer - and complained that, occasionally & randomly, it would not start. It seemed like the minivan's whole electrical system was dead... Brother-in-law was known to be "not so good" with cars - so his automotive engineer father didn't take the complaints serious…

I have a 2009 Mercedes SLK that had the same symptom. It was absolutely fine 99.9% of the time, but one time in a thousand it wouldn't even try to start. No clicks, no indication that it even knew I was in there turning the key. Just dead. And then seven or eight hours later... it would start fine, as if nothing ever happened. Couldn't correlate it to anything. Had it towed to a service center a few times when this h…

[deleted]

Re: Car allergic to vanilla ice cream (2000)

#102

Post by karmakaze »

maweaver wrote: post #34

> Moral of the story: even insane-looking problems are sometimes real. To me the moral of the story (and my experience) is: user's problems are usually real, but don't trust their ability to diagnose the actual cause.

Stated another way, distinguish observations (facts) of a story from the inferences--don't dismiss the observation/facts when rejecting inferences. This is analogous to an XY problem.

Re: Car allergic to vanilla ice cream (2000)

#103

Post by skipkey »

dumbfounder wrote: post #66

This is a secondhand anecdote, but it’s pretty funny. Back in the days of server rooms, a friend’s server for his company would reboot every day around 5pm. They checked everything they possibly could with the OS, they would be logged in and running checks on it and it would spontaneously go offline for about 5 minutes and reboot every day. Finally they decided to go stand in the presence of the server around the tim…

I personally had a similar situation. We had an accounting firm whose servers we were maintaining, and occasionally the print server would reboot, always between 9 and 10 am. So I sat in there for a week between those hours and noticed the light would dim and occasionally the reboot would happen.

It turned out that the lawyer next door would come in, turn on his PC, printer and coffee pot simultaneously because they were all on the same power strip, and the drain was causing an undervoltage on the circuit the server was on during startup. We had it on a UPS, but it turns out that at the time consumer grade UPS systems only handled outages.

I measured drops as low as to 85 volts, in practice anything under 95 or sou would reboot.

Re: Car allergic to vanilla ice cream (2000)

#104

Post by DoneWithAllThat »

addaon wrote: post #40
bell-cot wrote: post #2

This reminds me of a GM minivan that my youngest brother-in-law drove, back in the '80's. He'd gotten it from his father, who was a career GM automotive engineer - and complained that, occasionally & randomly, it would not start. It seemed like the minivan's whole electrical system was dead... Brother-in-law was known to be "not so good" with cars - so his automotive engineer father didn't take the complaints serious…

I have a 2009 Mercedes SLK that had the same symptom. It was absolutely fine 99.9% of the time, but one time in a thousand it wouldn't even try to start. No clicks, no indication that it even knew I was in there turning the key. Just dead. And then seven or eight hours later... it would start fine, as if nothing ever happened. Couldn't correlate it to anything. Had it towed to a service center a few times when this h…

I have seen similar behavior on vehicles that have a dying alternator. The issue is that one vane of the rotor (or maybe stator?) has shorted and no longer functions. If when the car is shut off and the rotor stops in a particular position the alternator won’t work. Give it some time and with heating/cooling moving things around just a bit plus the act of repeatedly trying to turn it on potentially making it move just a bit, and it works fine.

Re: Car allergic to vanilla ice cream (2000)

#107

Post by mavamaarten »

LanceH wrote: post #36

My wife's car right now is low on windshield wiper fluid. It warns us at a particular spot while we are driving. Not a particular distance from home, a specific geolocation. First thoughts were that it was the amount of time as she went to something and came back. But it does the on screen and audible warning at that location every time, no matter what was driven before that, whether it was 5 minutes, 5 miles, an hou…

I have a similar situation but in my case it's very obviously the gentle bend in that location combined with the relatively high speed that makes the fluid hug one side of the reservoir. I'm pretty sure that the sensor is mounted to the opposite side.

Re: Car allergic to vanilla ice cream (2000)

#108

Post by bhickey »

drivers99 wrote: post #78
dumbfounder wrote: post #66

This is a secondhand anecdote, but it’s pretty funny. Back in the days of server rooms, a friend’s server for his company would reboot every day around 5pm. They checked everything they possibly could with the OS, they would be logged in and running checks on it and it would spontaneously go offline for about 5 minutes and reboot every day. Finally they decided to go stand in the presence of the server around the tim…

Definitely an urban legend at this point. A reddit thread[0] mentions it being collected in 1990 from computer stories going around in the 80s[1] [0] https://old.reddit.com/r/talesfromtechsupport/comments/5yrs1... [1] https://www.goodreads.com/book/show/3227607-the-devouring-fu...

The story probably endures because things like this actually happen [0, 1]

0. https://www.cnn.com/2023/06/27/us/janitor-alarm-freezer-rens...

1. http://www.st-v-sw.net/Obsidian/Martin/gravity.htm (search sprinkler)

Re: Car allergic to vanilla ice cream (2000)

#109

Post by SketchySeaBeast »

iforgotpassword wrote: post #85
dumbfounder wrote: post #66

This is a secondhand anecdote, but it’s pretty funny. Back in the days of server rooms, a friend’s server for his company would reboot every day around 5pm. They checked everything they possibly could with the OS, they would be logged in and running checks on it and it would spontaneously go offline for about 5 minutes and reboot every day. Finally they decided to go stand in the presence of the server around the tim…

Man I've heard this story so many times, this guy must have a million friends in a hundred countries he's told this story to. :-)

The key to making friends is having a good story.

Re: Car allergic to vanilla ice cream (2000)

#110

Post by amluto »

LanceH wrote: post #67
pphysch wrote: post #39

Earlier quoted context omitted.

Is there anything notable about the terrain at that point? A sharp turn, bumpy road, etc.

Long slow bend on completely flat road, 40mph. No braking or acceleration for a quarter mile each direction. The road is like that for miles with some lights, traffic circles, etc... Only warnings in one spot. I really didn't believe my wife, or thought maybe it was happening a few times when she made a regular trip like getting drive thru coffee and coming right back. But then we ran a bunch of errands all afternoon…

> Long slow bend

That’s probably it.

If I were designing a wiper fluid warning, I would use some sort of fluid level sensor and I would denounce it aggressively: the indicator would only light up if the sensor detected a low level for more than a couple seconds. That way traffic circles, bumps, etc would not cause many false positives. I might even couple it to some kind of acceleration sensor so a warning would not turn on during or shortly after any heavy vibration or acceleration.

A long slow bend would cause a prolonged, steady centrifugal force and/or sideways acceleration due to a banked road, which would defeat these mechanisms.

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