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View Full Version : OT - worth a chuckle; problem fixation and car problems



mattthemuppet
02-13-2013, 11:12 PM
I've been lurking here a while since I was given a small and very old bench top lathe by a friend. However, this is something entirely unrelated and still makes me laugh.

A few weeks ago, the battery (at least 4 yrs old) in our car started acting up after spending at least a year on notice of needing replacement. The new battery seemed to fix the problems we were having (hesitation on cranking mostly, then not cranking at all :)) until a week later, when my wife called me at work to say that she was stuck in the library car park with our youngest and a dead car. I borrowed the bosses' car and went to the library, only to find the car almost totally dead. I hooked up the jumper cables from our trunk and switching on the ignition completely killed the electronics. No dome light, dash lights and the immobiliser light was barely visible. Hmm. Took the wife and youngest home so that she could be there when the eldest went back to school, then back to work.

After having dinner, I loaded up the bike trailer with every tool I could think of (bar one, very important one it turns out) and pedalled over to the library. Only 0C, so it wasn't too bum clenchingly cold. Tested the battery, read 12.5V. Yanked all of the main power fuses, all good. Took off the -ve terminal, cleaned it, put it back on and the dome light came one. Yay! Fixed it me thinks. Turn the ignition = dead car. Hmm. Started unbolting, cleaning and re-dialectric greasing all the ground straps, when a tow truck pulls into the carpack (he and a buddy are there to fix an outside sign light). He tries giving me a jump, but the car is still dead, so he says he'll come back in an hour after a call and give me a tow if I can't get it fixed.

I keep futzing around, with that "I just can't figure this problem out" sinking feeling, when the tow truck driver's mate comes over and we start going through the symptoms, what I've done and so on. He says it'll be worth hooking up the jumper cables just to see if we can get the lights on to check the basic function of the electrical system, so be brings his car over. After fiddling around trying to get a good connection, he hears an arc and figures out that the hot wire to the +ve terminal is loose (I forgot my 12mm wrench to take off the +ve terminal, so I never looked at it). He jams the wires in further and the car starts! I'm extraordinarily happy, shake his hand, jump around in joy a bit and then start packing up, with the car running.

THen, I start pulling off and the engine begins dying with anything more than a hair of throttle. Crap, I think, but it's late, the streets are fairly quiet and I should be able to nurse it home. I manage to get through a few junctions, before stalling on a slight incline at a stop light. Grr. I jump out of the car, wave the cars behind me past, dismantle the hotwire clamp and cinch everything up tight again. I manage to get the car started and, by pulsing the throttle and timing it right, manage to get through the junction without stalling. I get into 2nd gear and time the rest of the stop lights so I don't have to stop, get home and relax. Now that I've relaxed and stop thinking about the loose hotwire, I suddenly remember unplugging the mass air flow sensor to take the airbox out to get to a ground strap. What did I forget to replug? The mass air flow sensor cable - hence stalling the engine anytime more than a whiff of air went through it.

Plugged it back in, bought a $4 brass terminal clamp (the crappy OE lead one had bent enough for the clamped wires to break connection), a crate of beer for the tow company guys and it's been fine ever since. After all that time spent thinking about the ignition and battery, my nerve wracking ride home was entirely my own fault! After that, my dad sagely reminded me to replace the battery terminals any time I replace a battery. Thanks Dad :)

sasquatch
02-14-2013, 08:28 AM
Yup, been there also, good to just apply the process of elimination, but no fun at cold temps.

ironmonger
02-14-2013, 09:35 AM
It's hard to think of everything when you're cold and under pressure...

I had a Triumph Herald, and due to a dead spot on the starter commutator one needed to carry a small crescent wrench (adjustable spanner) to rotate the starter shaft ever so slightly to start the car. As one who used to service British motorcycles in my earlier years it's easy to see why we knick-named Lucas electrics the 'Prince of Darkness'. Considerate of Lucas to leave the square boss sticking out of the starter... how did they know that it would fail just that way?

A test drive down a unlit country road on a TT Special with no moonlight coupled with a failed Zener voltage regulator equals zero functioning light bulbs. Add that to 50+ miles per hour... it makes body parts pucker...

BTW usually some one will usually jump in and comment on the lack of location in your profile... but car park and +ve pretty much nails it down :rolleyes:

Welcome

paul

bborr01
02-14-2013, 09:54 AM
I've been lurking here a while since I was given a small and very old bench top lathe by a friend. However, this is something entirely unrelated and still makes me laugh.

A few weeks ago, the battery (at least 4 yrs old) in our car started acting up after spending at least a year on notice of needing replacement. The new battery seemed to fix the problems we were having (hesitation on cranking mostly, then not cranking at all :)) until a week later, when my wife called me at work to say that she was stuck in the library car park with our youngest and a dead car. I borrowed the bosses' car and went to the library, only to find the car almost totally dead. I hooked up the jumper cables from our trunk and switching on the ignition completely killed the electronics. No dome light, dash lights and the immobiliser light was barely visible. Hmm. Took the wife and youngest home so that she could be there when the eldest went back to school, then back to work.

After having dinner, I loaded up the bike trailer with every tool I could think of (bar one, very important one it turns out) and pedalled over to the library. Only 0C, so it wasn't too bum clenchingly cold. Tested the battery, read 12.5V. Yanked all of the main power fuses, all good. Took off the -ve terminal, cleaned it, put it back on and the dome light came one. Yay! Fixed it me thinks. Turn the ignition = dead car. Hmm. Started unbolting, cleaning and re-dialectric greasing all the ground straps, when a tow truck pulls into the carpack (he and a buddy are there to fix an outside sign light). He tries giving me a jump, but the car is still dead, so he says he'll come back in an hour after a call and give me a tow if I can't get it fixed.

I keep futzing around, with that "I just can't figure this problem out" sinking feeling, when the tow truck driver's mate comes over and we start going through the symptoms, what I've done and so on. He says it'll be worth hooking up the jumper cables just to see if we can get the lights on to check the basic function of the electrical system, so be brings his car over. After fiddling around trying to get a good connection, he hears an arc and figures out that the hot wire to the +ve terminal is loose (I forgot my 12mm wrench to take off the +ve terminal, so I never looked at it). He jams the wires in further and the car starts! I'm extraordinarily happy, shake his hand, jump around in joy a bit and then start packing up, with the car running.

THen, I start pulling off and the engine begins dying with anything more than a hair of throttle. Crap, I think, but it's late, the streets are fairly quiet and I should be able to nurse it home. I manage to get through a few junctions, before stalling on a slight incline at a stop light. Grr. I jump out of the car, wave the cars behind me past, dismantle the hotwire clamp and cinch everything up tight again. I manage to get the car started and, by pulsing the throttle and timing it right, manage to get through the junction without stalling. I get into 2nd gear and time the rest of the stop lights so I don't have to stop, get home and relax. Now that I've relaxed and stop thinking about the loose hotwire, I suddenly remember unplugging the mass air flow sensor to take the airbox out to get to a ground strap. What did I forget to replug? The mass air flow sensor cable - hence stalling the engine anytime more than a whiff of air went through it.

Plugged it back in, bought a $4 brass terminal clamp (the crappy OE lead one had bent enough for the clamped wires to break connection), a crate of beer for the tow company guys and it's been fine ever since. After all that time spent thinking about the ignition and battery, my nerve wracking ride home was entirely my own fault! After that, my dad sagely reminded me to replace the battery terminals any time I replace a battery. Thanks Dad :)

Matt,

I kind of hate to get between you and your dad but I think that replacing battery terminals every time you need a new battery is way overkill. I have replaced very few in many years of driving. This includes some old beaters.

Brian

A.K. Boomer
02-14-2013, 10:23 AM
Look at it this way, never before has your car achieved that kind of fuel economy,

you actually inadvertently pulled out a hail mary in one of my bag-o-tricks, it's what you do in a rural area (so you don't hold up traffic and can retain smooth driving) when you find yourself 30 miles from home and you know you only have about a half gallon left in your tank,

Unplug your airflow meter, then you keep the engine on the verge of falling on it's face and then back off a smidge - it's not good practice as it's extremely lean but you have two things going for you, it's a short trip and your not making enough power (your basically just running off of an idle circuit) to melt a hole in your piston or toast an exhaust valve, if you have concerns then run for 15 minute intervals and then let sit for 15 minutes,

if you can average 25 or 30 miles an hour it sure beats walkin...

not all cars have an air flow meter - you might be able to achieve the same kind of results with a TPS (throttle position sensor) but you can't just unplug it, you have to leave it plugged in and physically remove it from the throttle, iv never tried that one and that's what my current car has - but, in theory it should work if you happen to have the tools with you at the time,

keep in mind all systems are different.

if you unplug or disconnect anything and you don't get the "lean bog" results then plug everything back in and take your chances, some systems automatically go to a fail-safe - what this means is that instead of fooling your computer your computer will compensate with a clumsy calibrated extra rich mode and you will be far worse off than if you just left it alone...:eek:

bruto
02-14-2013, 11:20 AM
I had an odd one recently. I have a Gm truck with a side terminal battery. It took a charge well, ran fine, and every once in a blue moon would be stone dead, and not take a charge. I'd replace the battery with a spare (worked fine) and then test the old one (just fine) put it in and it would be fine, until at some random time it would go dead again. It flummoxed me for some time, until I yanked on a post one day and it came apart. The connection inside the battery case had broken invisibly. Mechanical movement would open and close the connection.

mattthemuppet
02-14-2013, 11:43 AM
thanks for the kind words everyone (location now added too :)). Electrical problems always flummox me and add to that the thought of having to spend $100s of dollars on a tow/ garage work, plus working in the dark really didn't help. It was one of those things that any competent mechanic would have picked up immediately, but it's something I've never come across before. I'll definitely remember it in the future, even though it's now very unlikely I'll ever need that knowledge (hopefully)!

Brian, yeah, I'm sure it's overkill, but it would have saved me a whole lot of stress if I had done it :) The -ve terminal was fine, but the +ve one was all bent and deformed - the hotwire clamp holes were even starting to enlarge to the side.

Boomer, he he he, that made me laugh. That would certainly make for a terrifying ride, just 2 miles was bad enough. Then again, I always keep a gallon container of petrol in the car, so hopefully I'll never have to (fingers'n'toes crossed)

Bruto, I hate intermittent electrical problems like that. Trying to figure out what's going on is a real tough one. Glad you got it fixed though!

michigan doug
02-14-2013, 09:11 PM
Poking, wiggling and tugging turn out to be surprisingly effect at troubleshooting many electrical gremlins in a vehicle.

Git-er-done,

doug

Don Young
02-14-2013, 10:52 PM
Since they replaced the heavy top straps with internal straps which are spot welded together through a hole in the case wall, broken and intermittent internal battery connections seem pretty common. I had one that cranked the car but when the engine slowed down to shift to second gear, it died from loss of ignition. There was absolutely nothing from the battery.

Those internal bad connections also are prone to causing batteries to explode. I had that happen to one while being charged.

flylo
02-15-2013, 12:07 AM
I've used screws between the top post & the battery cable end until I could get proper tools or parts.

Tony Ennis
02-15-2013, 12:16 AM
One day a friend was having trouble with his battery not holding a charge. I gave him a jump... and the jumper cables melted. Apparently he had a short of some sort in his battery.