All Questions
26,898
questions
119
votes
9
answers
66k
views
Why is plexiglass not used for car windows?
Back in 2014 someone broke the right side window of my VW Golf.
I was in a hurry and short on cash so I "temporarily" cut a 4 or 5mm thick piece of plexiglass ($8), bent it with hot air and placed it ...
- 1,373
104
votes
17
answers
272k
views
Does Downshifting (Engine Braking) Cause Extra Wear and Tear?
Does the act of downshifting to slow your vehicle down have any negative side affects?
I don't downshift more than one or two gears at a time and I let out on the clutch slow enough that I don't rev ...
- 1,193
90
votes
14
answers
26k
views
Why don't we rotate tyres but you rotate tires?
Is planning a regular rotation of new tyres over their lifespan a good or bad plan?
From many posts I've seen here and elsewhere on the web, motorists in the USA seem to see rotating tires as a task ...
- 23.5k
89
votes
13
answers
101k
views
Does the amount of fuel in the tank matter?
As long as there is some fuel in the tank, does the fuel level matter? In other words, is it advisable to make sure the tank is mostly full most of the time, or is this just silly? In other words, are ...
- 993
82
votes
10
answers
46k
views
What are the benefits of premium (high octane) petrol?
Here in the UK it's common for petrol (gas) stations to offer both regular and "premium" unleaded petrol. The premium stuff is (naturally) more expensive, and I've often wondered what the actual ...
- 1,053
77
votes
21
answers
82k
views
How can I keep stray cats off my car?
We have a lot of stray cats in my neighborhood and they possess an uncanny ability to know when a car has been cleaned for them to sit on and enjoy.
Needless to say, the dirty, dusty paw marks they ...
- 39.1k
76
votes
16
answers
525k
views
Should I resurface or replace my rotors everytime I replace brake pads?
I have heard it is proper practice to replace or resurface your brake rotors every time your do a brake pad replacement. Does this need to be done every single time or is it overkill? Maybe it is ...
- 2,096
71
votes
6
answers
390k
views
Why does my A/C blow foul smelling air when it first turns on?
Most of the time when I first turn on the A/C in our 2008 Toyota Sienna, the air that blows out has a very distinct chemical - nasty smell. After a while it seems to go away. I'm not sure if I just ...
- 813
70
votes
15
answers
36k
views
Are classic cars safe?
Are classic cars safe? I am interested to know the differences between modern vehicles and vehicles of old from the 1960s.
In the event of an accident, how does a classic vehicle compare to a modern ...
- 4,730
68
votes
7
answers
23k
views
What to check when buying a used car?
I'm looking to buy a used car. What do you think I should check (mechanically) before buying it (especially if it's diesel)?
- 1,021
66
votes
9
answers
810k
views
What actually happens when there is not enough oil in a car engine?
When a car is topped up with oil, it clear to most people that you are supposed to fill it to the recommended amount as specified by the manufacturer (normally on a dip stick).
What exactly are all ...
- 7,927
62
votes
6
answers
10k
views
How to maintain a sometimes-used vehicle?
My daily commute changed from 9 miles to 9 feet when I started working remotely. That means I very rarely drive my car much. After a particularly hectic month, I didn't drive for about 4 weeks and ...
- 1,009
62
votes
6
answers
311k
views
How long does it take for gas to go bad?
Approximately how long does it take for unleaded gasoline in the tank and fuel lines to become unusable in a car that is not being used? What causes this, and what can be done to prevent or remedy ...
- 2,591
59
votes
6
answers
55k
views
Why do heavy vehicles almost always use diesel engines?
I have always wondered why heavy vehicles such as large trucks and buses almost always use diesel engines, whereas in light cars there is a choice between diesel and gasoline engines.
Engine ...
- 14.5k
56
votes
22
answers
202k
views
Effective way to clean inside of windshield?
The inside of my windshield has a thin layer of grime. When the light hits it a certain way, it drastically reduces my visibility.
I have used glass cleaner with clean microfiber car cloths and ...
user11271
51
votes
6
answers
14k
views
What is the most efficient method of getting your car unstuck from snow?
If your car is stuck in snow and you don't have any chains, what can be done to get it out? This can be an unnerving problem to have and it happens pretty easily with normal driving on ice. You wind ...
- 33k
51
votes
4
answers
88k
views
Reviving a vehicle that has been idle for a long time
Some related topics:
How to maintain a sometimes-used vehicle?
How long does it take for gas to go bad?
The first related topic addresses preparing a vehicle for long-term disuse, and maintaining ...
- 2,591
50
votes
6
answers
16k
views
Why don't rally cars have airbags?
Why don't rally cars have airbags?
Other competition cars, including Ken Block's don't have airbags either.
Is it just for weight reduction, are they redundant or is there another (major) reason?
- 1,006
47
votes
14
answers
12k
views
How do I save myself from a sinking vehicle?
Every year in Arizona there are monsoon storms and somebody inevitably get's killed in a car that is sinking in water.
It appears the primary issue is getting free from the vehicle. After that, ...
- 33k
46
votes
4
answers
26k
views
Jump starting a dead battery: Connect black wire to negative pole of battery or grounded metal?
Most of the advice I've seen for jump starting cars instructs to connect the black wire to a bare piece of metal on the car with the dead battery. However, I've always just hooked up both poles to the ...
- 768
43
votes
4
answers
157k
views
How far can I drive with 1 gallon too much oil?
I have way too much oil in my Acura TSX. Do I need to take care of it without turning it on or can I drive it to a service station?
If I need to do it in place, I don't have the ramps or a pan or ...
- 665
43
votes
3
answers
137k
views
Is there a way to put Prius with dead battery into neutral?
I own a 2010 Prius. It has a dead battery, front facing forward in my garage. I do not have long enough jumper cables.
I’ve searched the Internet. Did Toyota really create a car that cannot be put ...
- 533
42
votes
15
answers
57k
views
Why don't people hand pump their tires?
My bicycle tires go to 60 psi, and I can easily fill them up from nothing with less than 10 pumps.
My car tires are at 32 psi, so shouldn't they be even easier? Yet I have never heard of anyone hand ...
- 487
42
votes
7
answers
640k
views
what is the difference between DOT3 and DOT4 brake fluids?
What is the difference between DOT3 and DOT4 brake fluids?
What could possibly go wrong if I use a (4 times cheaper) DOT3 brake fluid instead of the DOT4 which manufacturer recommends (but allows ...
- 1,344
41
votes
9
answers
573k
views
When do brake rotors really need to be replaced?
I need to replace my rear brake pads. A mechanic suggested I also replace my rotors because they are rusted around the edges. The rotors are in fact quite rusted, however, there is no rust on the ...
- 513
40
votes
10
answers
84k
views
How do I remove a destroyed lug nut?
A neighbor friend of mine offered to change my brakes on my Pontiac Torrent, well my husband had the proper tool to remove the lug nuts off my car in his truck, and the neighbor along with some other ...
- 403
40
votes
6
answers
47k
views
Why is a motorcycle's neutral between first and second gears?
The gear pattern is selected by clicking a lever with your left foot and is typically laid out as follows:
6th gear (if applicable)
5th gear
4th gear
3rd gear
2nd gear
NEUTRAL
1st gear
What is ...
- 579
40
votes
10
answers
68k
views
Is it necessary to 'burn in' or 'break in' a new car?
I've just bought a new 2011 plate car. I've heard stories of people 'burning in' engines for the first few hundred or couple thousand miles using methods such as:
Not driving above 50 mph.
Varying ...
- 503
39
votes
8
answers
16k
views
Is tire rotation important?
I just bought new tires for my car and included was free tire rotation every 7,500 miles for the life of the tires.
I have heard many things about tire rotation, including:
it's a worthless practice,...
- 493
38
votes
12
answers
17k
views
Does kicking a tire off your car from underneath it while it's held up by a stable jack pose safety threats?
I just had to put a doughnut on my car and I used the typical manufacturer car jack that fits into that little slot of metal near your wheel. After I got all the lug nuts out, I tried pulling the ...
- 489
38
votes
3
answers
374k
views
What does a water-like drip coming out of the exhaust of the car signify?
Sometimes while driving in the traffic, I come across a car or two which would be dripping water-like drops from its exhaust steadily in 4-5 second intervals. I tried to ask a couple of people at the ...
- 685
38
votes
3
answers
79k
views
What's the Purpose of Park on an Automatic Transmission?
When one wants to park a manual transmission (MTX) vehicle, one puts it in neutral, and engages the emergency / parking brake. With an ATX vehicle, the practice I've learned is to put it in Park, and ...
- 15.7k
37
votes
5
answers
96k
views
What are the benefits of a lightweight flywheel and why aren't they lightweight already?
This previous question explains what a flywheel does and why it is needed. That explanation means that the flywheel needs a certain amount of mass to do its job. However, an "upgrade" for many cars (...
- 13.3k
37
votes
3
answers
8k
views
Changing Firing Order in a 4 Cylinder Car
Backstory
In motorcycling you can get cams that change the firing order and time from a traditional 1,3,4,2. It's was very common in American road racing in the 1990's to hear 4 Cylinder engines that ...
- 33k
36
votes
11
answers
15k
views
What is in fossil fuels that we can't mass produce?
Since fuel is made up of different molecule chains, my question is what is the reason we cannot create the same molecule structure and be able to reproduce the same structure in a lab so we don't have ...
- 1,691
36
votes
8
answers
13k
views
Do I really need to wash the outside of my car?
Some people say they wash the outside car every week as it makes the paint nice etc
Are there any benefits of washing the outside of my car?
Do I really need to wash the exterior of my car every ...
- 6,555
36
votes
6
answers
83k
views
Why doesn't anyone ever repair an automatic transmission?
I am old enough to have had about four transmission failures spaced over about 40 years and at no time did any mechanic ever offer to “fix” it; the only diagnosis has been a complete rebuild.
This is ...
- 462
36
votes
3
answers
13k
views
Why are the blades of car radiator fans unevenly spaced?
Fans that look like this:
Is it to somehow help the balance of the engine?
- 1,698
35
votes
8
answers
18k
views
Why do manufacturers detune engines?
I was wondering why a manufacturer would detune an engine. An example -- there are many others -- is the Mercedes-Benz OM612 engine. Same engine, lower (peak) power output in the Sprinter than in the ...
- 1,135
35
votes
1
answer
7k
views
Why is my car equipped with a battery shutdown timer?
I currently live in Japan where I bought a 1997 Subaru Impreza WRX STi. Since I don't completely speak Japanese, I wasn't able to ask anybody correctly about one thing that the previous owner had ...
- 467
34
votes
10
answers
29k
views
Is it safe to use a hydraulic jack as a stand? If not, why?
"If a jack can lift a load, surely it can withstand the load for extended periods of time?!"
I've come across some conflicting ideas regarding this subject:
The user guide for my low-profile ...
- 39.1k
33
votes
7
answers
12k
views
What is the point of the exhaust?
I was thinking today, what is the actual point of an exhaust?
Why can't we just have a pipe going out the front of a car instead of taking all the gases to the back of the car?
I can only see ...
- 6,555
33
votes
8
answers
421k
views
Running with straight water as coolant in the summer. Is it fine?
I grew up flushing the coolant twice yearly. In the Spring, you drain the antifreeze and fill with straight water for the summer. In the Fall, you drain the water and put in a 50/50 antifreeze/water ...
- 695
33
votes
12
answers
80k
views
Can a vehicle be harmed with bad inputs via an OBD-2 port?
I bought a cheap (sub $10) ELM 327 Bluetooth clone OBD-2 diagnostic adapter on a local "ebay-style" market where the seller specializes in car diagnostics and has several thousand positive reviews (...
- 1,305
33
votes
3
answers
15k
views
Difference between FWD/RWD/4WD/Part-Time 4WD/AWD?
I'm curious as to what are the particular difference between the various drive systems available in modern vehicles. FWD and RWD are pretty straightforward - Front Wheel Drive cars put the power to ...
- 2,591
32
votes
11
answers
60k
views
Spark plug broke off in engine - can I drive the car?
I own a 2004 Volvo XC90 T6 2.9L AWD with 6 cyl. (Twin turbo, with catalytic converter.)
While changing the spark plugs, one broke-off (all the ceramic below the threads and possibly the metal finger ...
- 321
32
votes
8
answers
24k
views
Is it necessary to have the wheels of a car aligned with the body when parked, due to weight on the axle? [duplicate]
My uncle says a driver advised him that whenever the car is parked, the wheels have to be aligned with the body of the car, or else there will be un-necessary weight on (I think) the axle or wheel, ...
- 1,441
32
votes
6
answers
49k
views
Could a car left sitting for 6 years ever run again?
First time posting, let me know if I'm doing everything right!
We've got a '92 Volkswagon Cabriolet, with 175K+ miles on it, that's been sitting in the garage since 2010. Wheels are all flat, and I ...
- 321
32
votes
2
answers
67k
views
Difference between OBDII and CAN
What is CAN (controller area network)?
What are the differences between an OBD-II protocol and a CAN setup?`
How do I use an OBD-II scanner on a vehicle with CAN?
- 8,956
32
votes
6
answers
556k
views
What causes battery terminal corrosion?
I put a new battery in my car about 8 months ago. After a problem starting a couple days ago, I found that there was massive corrosion under the battery terminals, so I cleaned them out and ...
- 12.5k