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Mysterious faults on cars, as well as other car stuff (and other automotive)

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fezder

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I didn't place this thread to automotive-section as this sin't problem-related. We just had slight talk about cars with spec
So, feel free to let some steam about automotives and tell about mysterious faults, maybe we get couple new ideas as well as few good laughs.
Moderators, feel free to close thread/move it if needed :)
 
Hi Fez,

Good thread :)

My feeling about cars is love/hate. This whole car thing has got totally out of control. In the UK, for example, the car is the second most expensive item after a house. That is crazy. They are so complex these days, mainly due to the rediculous regulations, much related to the global warming religeon.

People actually spend around £16K on a car and the moment it is driven off the forecourt, it has lost 20% of its value

They then expect to buy another car in 2 years time and start the whole process all over again.

In the 1980s, if a wing mirror got ripped off, you went to the local auto store and bought a replacement for a couple of quid. It then took 20 minutes to fit. Someone hit the mirror on my son's BM the other day. The mirror was £280 and spraying and fitting was another £120- just for one mirror! On my 1980s granada if a dash light failed the bulb was £0.33 and you could fit it in 5 minutes without any tools. On some cars now you have to take out the wholes dash just to replace one bulb- total madness!

I will stop now :eek:
 
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it's like one mechanic told me once: cars are desgned outside-in; first appearance, then all else.
 
Cars are designed for quick and easy assembly in the factory.
Quick and easy assembly = slow and expensive maintenance.

JimB
 
Yeah, i supose this applies to anything that is made in factory? at least aim is to reduce costs in produce, lifetime isn't that much of importance

EDIT: well not all appliances perhaps, like medicinal gear
 
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A 1980's Toyota:
If the car was warmed up and turned off for about 20 minutes and restarted, the idle was really rough.
Turned out to be a solenoid valve mounted on the valve cover (Hot area) that opened the EGR full to stop dieseling.
This was an extremely difficult problem to find. I did roadside troubleshooting when the problem occurred a few times.

Same Toyota. The car died near a bunch of junkyards. I had tools with me. I was able hitch a ride, grab an later model module and drive home (40 miles) using a few alligator clip jumpers. In the same general area I had my car broken into and the tools stolen on a rainy day with an alarm system and me coming out as they were running away. So much for alarm systems. The was the Philadelphia area.

To fix a water leak (I had thought it was a head gasket) only to find that a really tiny length of hose under the intake manifold had a hole in it. A lot of work for nothing,

Friends borrowed my car an left it running with the keys in it. At one point, I went swimming with a girlfriend and locked the trunk key in the truck with our outer clothes.

I was in Philadelphia and had my car amplifier replaced by an equivalent weight of Lentils.

On the way to Virgina, USA, my clutch started to slip. I chanced crossing the Chesapeake Bay Bridge Tunnel (about 20 miles long, no shoulders). I safely got to my destination and my uncle said do what you can and I'll help when I get home from work.
He had an I-beam chain hoist.
Well, I forgot to drain the oil from the transmission. I found a BIG BOLT missing which was the likely cause of premature clutch failures. I called a dealer and asked if they had a clutch in stock. They did. By the time I got there, the service department had used it for another car. Elapsed time, about 45 minutes. Anyway, my uncle used two connected dissimilar sockets as a clutch alignment tool.

I my younger days, I helped someone get their car running with a milk junk and a hose. The fuel pump broke, so the milk carton became the gas tank in the engine compartment. They were elated.

I took an exit too fast and ended up in stuck in deep MUD off an interstate when it was raining. I used my car mats and got out.
So, that's what there good for. Used them for snow issues too.

Car/road erosion: I blew a tire, bent a rim and the 3 out of 4 trim rings decided to pop off the wheels when the edge of the road was mysteriously missing because of erosion.

I was driving. A cop stopped me and warned me of the snow. I came back the same way and found him on the snow bank.
In another incident I saw a car doing donuts in front of a donut shop in the snow. 5 cars were able to not to the car. One guy hits us all. The cops said, we're too busy. No one''s hurt. How about driving to us. We're a couple blocks down the road.

I just got my license and basically rebuilt a car that was wrecked. Cost of the basic car was $25.00 USD, I did port the intake manifold, added electronic ignition and had the heads re-built. I got 18 mpg on a 1965 6 cyl vehicle. One bug was really tough and i was probably 15 YO at the time. The fuel line had a slit in it at the tank. There was a tank to metal tube rubber hose coupling there,

I had an engine fire from a stupid Holley carb. The carb liked to lose it's accelerator pump linkage. I sacrificed a jacket and put the fire out easily.

Driving along the road, a deer stopped in front of me. I turned off the lights (1980's vehicle). Deer went away and we were both happy. Do, you know how hard it is to turn off the lights in the dark in a modern car?
1) In one case it's turn off car, open door.
2) The other is a bit more difficult because of the headlights stay on for 5 minutes after you turn off the car, so it's
a) turn off car(lights are still on), b) apply emergency brake, c) start car (lights now off), d) remove emergency brake.

A car just stops periodically about 20 minutes after starting. Wait about 10 minutes and it just starts back up. Ignition pickup,
No codes in this model. Electronic ignition, proprietary diagnostics.

What do you do when a bridge is solid ice before you? Well, somebody behind me slammed on the brakes. That was the wrong thing to do. That bridge was short. I drove on an interstate bridge that was solid ice too. It was fairly long and there was little traffic at 4:00 am in the morning.

I did a mechanical fuel pump change along the side of the road (development). The occupants gave us some ice tea. Gravity wasn't on my side. The "trick" is to put grease on the rod that activates the pump, so it doesn't fall out. It's kinda like "Don't remove this screw in electronics".

I replaced the pop-up headlight wires with test probe wire. I prepped a vehicle for a cheap paint job with MAACO and they did not use the clear coat that the paint system required. They blamed me for the bad paint job. My prep, I did way too much prep. I even knew to etch bare metal.

Exhaust pipe fell. I fashioned a bracket with my socks.

One radio in a car has a temperature problem. At a certain temp around 60-70F it sometimes refuses to work. I got a replacement amp ($15.00 for a $300 USD factory amplifier) from an online junkyard and it has a different problem. Front speakers are distorted. Neither amps are fixed. Do have a service manual. The effort to rig up the harness is really excessive.
There's like a 25 pin connector and a 9 pin power connector. This amp "tells' the radio to put out a low or speaker level signal with a resistor. The amp is also used for chimes, etc. The radio sucks.

Besides that, the one problem is intermittent. Need the radio for the GPS.

Nearly the same sort of issue with an auto-dim mirror. Really cheap. Wrong one, then "better one" but still broken. Advice is just to get them rebuilt for about $120 USD. I added a piece of Kapton tape over the sensor to modify the response of the new material. I used sunglass material for another car just because I didn't like the response. The rebuilt mirror still has to be glued together. I got the glue from the rebuilder. They won't tell me what they use. Still not fixed. I'm using mono-filament fishing line to hold it together.

One vehicle had a bad blower resistor. I could not find a metric swivel socket to fit, so a 45 minute job took 3 hours. Turns out that, It turns out, in hindsight, that 5/32 is really really close to 4 mm.

Although not car related, it's important. A company rebuilds vintage oven thermostats and I was challenged with replacing one, You have to get this big sensor through a double wall at an angle. I was able to thread a drinking straw through both holes then tread the sensor through the straw and then cut the straw away.

Update Wed Dec 23 18:41:56 EST 2015
Turn signal would not work sometimes. Eventually found you could operate the hazzard swich and make the turn signals work. Replace hazard switch.

Car blower would slip out of it's friction mount. If left that way, it will take out the brushes. Push on it every once in a while. With brushes from a vacuum cleaner parts store and some brass shim and a file I was able to make the brushes fit. Motor was like $120 USD. Brushes about 1/20 of that.
 
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1. I have an old Toyota Camry with low mileage driven by a little old lady ( my mother when she was 92)
WHen the weather is cool and damp, the 4 cylinder engine runs on 3 until it warms up fully.

Problem creapage shorts on fuel injector voltage coil from engine contamination and moisture.
Solution : an engine car wash around the injectors every couple years.

2. in 1970 I had an MGB convertible in Winterpeg.
One eve coming home from university during a mid-winter storm, with -30'C wind chill and 1~2ft drifting snow across one highway, the engine died.
I'd prop open the bonnet (hood) and try the solenoid switch by the engine, It turned but wouldn't ignite. A minute later it started like there was no problem. so .. I drove off and managed to plow thru the snow and it died again.
Again I propped up the hood and again it wouldn't start for another few minutes. and I drove off.
The 3rd time, I got suspicious and looked closely as I was pushing the solenoid button with ignition on and saw corona around the distributor cap.
Luckily I had WD40 in the back and cleaned the Distributor cap and it worked fine after this.

Problem: dust creapage arcs on Dist. cap exterior with moisture that had shorted out the spark.
But when -30'C and hood open with blowing wind , it froze in a minute and then became an insulator
Solution get a new cap after driving safely home. No cell phones back then, so WD40 saved my life.
 
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I have same faults occuring with mine. Brushed motors get oxidized, escpecially windscreen cleaner fluid pump
this happens about once per year: completely unusable
**broken link removed**
once i repaired this motor by letting it soak in citrid acid, and it needed new brush-spring after that. Luckily i found suitable from my srap-box.

Another annoying problem involving brushed motors was when i was driving windows open (electric) and when i saw storm was coming, well windows didn't even budge.....
Next day, problem was solved with hammer: couple small taps on both motors, brushes were stuck.
Speaking of hammer, that is quite much all te time with me, as rear-brakes are stuck, more in winter. Drum brakes, so they'll stuck quite a lot (i live next to lake, so weather freezes brakes)
Speaking of freezing, many times i had to maneuver to drivers seat from passengers seat, as drivers door was frozen....waiting for that day when i have to go inside from trunk :D
Also, my front brakes were so used once that they dropped out in pieces when changing tyres.....or perhaps weather had killed them.
IAC valve gives problems once a while, idle rpm wanders between 1k-2k. Solution is just lubricate IAC shaft.

Had interesting day one summer when there was hot, hot summer day. Alternator decided to put 18 volts to 12 volt battery.....well, i had to drive home with all heating systems on, as well as other appliances on.
Nearly home, i had to put heating off, and pow, voltage dropped to 10-11 volts. That was the end of alternator

Clutch had interesting fault: if feet slipped from clutch pedal, clucth dropped out from it's place, cable i mean. We figured to repair it to stay put with zip-ties. Worked, but one day i was coming home from doctor, i felt that clutch was losing strength somehow, and soon it was gone; at up-hill. Luckily i take much speed to take uphills better, and i managed to get on top of hill, at the next intersection where i had to ask couple bypassers to help pushing my car to near gas station. Called my brother to get me home, andwe then noticed that clutch's cable was fine; but that extension that connects the cable to clutch was severed in half

and while ago, coolant fan went on same time with motor started, if motor had strength to start same time. Solution and finding faulty component was to fool computer to think that coolant temperature is ok, by placing 10k resistor in sensors place;
**broken link removed** other way around was when coolant fan didn't start at all last summer, hard-wired switch to turn on fan manually when needed. Can't recall what was faulty component back then, it wasn't relay but some odd component...
 
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EEEK! Just this summer, the power windows wouldn't work on a hot day, I worked in the morning. I drove for about an hour and it still didn;t work. It got cooler and I drove in a cooler area and it fixed themselves. I suspect thermal overload (Those PTC things) kicked in.

Speaking of brake systems. I had a failure where a piece broke and I lost all pedal braking. No dual master cylinders in a 1965 vehicle. Drove home (15 miles or so) with only the emergency brake cable to stop.

The mysterious blinking headlights:

Filament shorted. Thermal fuse in headlight switch caused the blink. About 1 in 30 seconds.
 
2. in 1970 I had an MGB convertible in Winterpeg.

Problem: dust creapage arcs on Dist. cap exterior with moisture that had shorted out the spark.
But when -30'C and hood open with blowing wind , it froze in a minute and then became an insulator
Solution get a new cap after driving safely home. No cell phones back then, so WD40 saved my life.

Modern cars have one coil per spark plug, mounted on top of the spark plug so really no HT lead and certainly no distributor, so the problem has been engineered out in the first place.

If customers and regulation would accept the lack of features of a 1970's car now, they would be almost perfectly reliable. However, the list of features needed by legislation or demanded by customers is ever increasing, so there is always more to go wrong. There are lots and lots of systems, and most of the things that might go wrong are found during testing before customers even see the cars. There are also quite rigorous standards that the manufacturers impose on the electronic systems to make sure that the systems survive extreme conditions. For example, one manufacturer demands that the electronics can survive:-
9 - 16 V (working)
Correct operation of electronics, no matter how the voltage turns on (slowly, quickly, noisily)
-40 °C to +75 °C or higher for full operation, depending on position in car
Reverse battery for 1 minute
28 V for 1 minute (jump start from 24 V lorry)
36 V for 1/2 second (alternator load dump)
Electrostatic discharge (depending on where in the car the electronics is)
Any connection to survive permanent connection to earth or positive.

The result is that the faults that are seen are getting more and more obscure and on a wider variety of systems, so when fault occur they are more difficult to diagnose.

The rapid development of new features has meant that diagnosis has lagged behind, and there have been lots of false warnings of faults. Also some electronic systems have been poorly designed for real-world conditions.
 
My previous car, Ford Fiesta assembled in Brazil, used to loose power (RPM coming down to 0) at any moment with no warning, no matter at what speed I was running. The worst ocasion was in a congested road between two trucks at 110++ Km/h. I had to escape to my right, lucky enough that no colision occured; just a very bad moment.

I finally managed to have the car sent to their local plant where it took them 1 month and 2.000 Km to solve the problem. They told me on the phone it was a bad connector. (?)

In the whole process, they never put a single email mentioning not even the word "failure" or equivalent. Even the truck that returned my car to the garage did not ask a signature for receipt.

Every time I tried to contact the Manager in charge of Customer Service, surprisingly, he was not available. Reasuring experience.
 
Blunders from the drawing board you say...

Had a 1979 Chevy Monza 2+2 hatchback, 305 cu. in. engine. It was a V8.
Anyways it used to cost an extra $85 to change the drivers side firewall spark plug during tune ups.
The reason why was although the car was an engineering masterpiece on the drawing board. In practical terms for the mechanic it was a nightmare.
The last spark plug on the drivers side by the drivers compartment was too tight get your hand in and fit a wrench socket on the spark plug. Never mind taking off and putting on the rubber boot for the spark plug.

The tuneup were $85 higher than other 305 based engines. The $85 fix was to undo the left motor mount. While the car was on a hoist. Then place a large 4" x 4" x 4 foot post under the oil pan and gently let the car down on the hoist till it twisted the motor to allow the mechanic to get his had down from the top while standing on a step ladder. Then bolt it all back up and proceed with the tune-up. About 1 year later MAC tools or Snap-On came out with a flexible goose neck attachment to fit the socket on the ratchet wrench. It was able to fit in the gap the hand could not and remove and replace the spark plug. However the cost of tuning the Monza never came down.

Nice car otherwise.
 
A 2000 Impala has almost the same issue.
An '84 Celebrity you had to take the wheel off to change the oil.

=

Connectors are the root of many evils.

Are they doing 1 coil per plug now rather than one per two plugs where it also fires in the exhaust stroke?

=

Computer controlled engines definitely improves the driveability when cold. I had a 73 Chevy product with so much extra "junk" on it for the early emission controls and carburated. Yuk!
 

My previous car, Ford Fiesta assembled in Brazil, used to loose power (RPM coming down to 0) at any moment with no warning, no matter at what speed I was running. The worst ocasion was in a congested road between two trucks at 110++ Km/h. I had to escape to my right, lucky enough that no colision occured; just a very bad moment.

I finally managed to have the car sent to their local plant where it took them 1 month and 2.000 Km to solve the problem. They told me on the phone it was a bad connector. (?)

In the whole process, they never put a single email mentioning not even the word "failure" or equivalent. Even the truck that returned my car to the garage did not ask a signature for receipt.

Every time I tried to contact the Manager in charge of Customer Service, surprisingly, he was not available. Reasuring experience.

Lesser problems like this have caused better companies $xxx millions in class action payments . This is how companies reduce their insurance costs. Big companies have many full time lawyers working many cases EVERY DAY.
 
Had a 1979 Chevy Monza 2+2 hatchback, 305 cu. in. engine. It was a V8.
Anyways it used to cost an extra $85 to change the drivers side firewall spark plug during tune ups.
Nice car otherwise.

I recall having the same car.
A Chevy Vega chassis with a V8 .
ya, Drop the engine, just to change the plugs.
and, change the front disc pads every year from excess weight.
 
In case of dead battery, no charger and urgent need.

Required:
- awareness of AC power risks and safe use
- 15A or more power diode, hookup wire
- one toaster (1800W)
- Connect neutral to chassis (-)
& hot thru toaster and diode to (+)
wait 5~10 min. start car.

Techie details.
High Voltage & Nichrome heater wire resistance acts as current source but with 1 diode only half power.
At no time was car at risk of high AC voltage since toaster drops it down to Vbat.
 
... more in winter. Drum brakes, so they'll stuck quite a lot (i live next to lake, so weather freezes brakes)
Speaking of freezing, many times i had to maneuver to drivers seat from passengers seat, as drivers door was frozen....waiting for that day when i have to go inside from trunk :D
...

That's why I moved to Arizona...
 
In case of dead battery, no charger and urgent need.

Required:
- awareness of AC power risks and safe use
- 15A or more power diode, hookup wire
- one toaster (1800W)
- Connect neutral to chassis (-)
& hot thru toaster and diode to (+)
wait 5~10 min. start car.

Techie details.
High Voltage & Nichrome heater wire resistance acts as current source but with 1 diode only half power.
At no time was car at risk of high AC voltage since toaster drops it down to Vbat.
What do you do with the toasts?
 
Don't even get me started...

In the end, all my cars, since 1971, have been used, cheap and at the least run and will move/stop. I rarely wash them (the dirt protects the wax) and many features don't work, in which case I then decide I don't need that/those feature(s) (ABS? Who CARES... - One fan speed?. Beats none!).

Have saved a boat load of money over the years and not one (ever) has one of them been broken into (too scary, I assume).
 
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