Skip to main content
46 votes
Accepted

If I am just replacing the car engine, do I need to replace the odometer as well?

I wouldn't touch the odometer. The rule I always subscribe to is that the odometer measures how far the chassis has rolled. Otherwise a person could go mad trying to figure out which repairs/...
smitelli's user avatar
  • 574
35 votes

Are car batteries meant to be disposable or are they re-chargeable?

Car batteries are not only rechargeable but are constantly being recharged by the alternator. Simply starting the car takes a lot of power reserves from the battery, then electrical systems such as ...
Steve Matthews's user avatar
33 votes

What is the small metal square attached to the wheel or tire?

Those appear to be wheel weights. When mounted on the rims, tires are often not totally and absolutely balanced. When you drive, it may cause all sorts of shaking issues if it is badly out of balance....
Blackbeagle's user avatar
30 votes

Why do car starter motors draw so much current?

All electric motors consume more current at startup compared to steady state. Check out the label on your fridge for example (or look at this one): the max current on the label is 2-3 times higher ...
Dmitry Grigoryev's user avatar
27 votes

What is the small metal square attached to the wheel or tire?

This is a wheel balancing weight. This type is held onto the inner side of the wheel with double-backed foam type adhesive tape. The the "1/4" stands for one quarter of an ounce. The "FE" denotes ...
Fred Wilson's user avatar
  • 11.6k
25 votes

How slow ( not zero) can a car engine run without hurting engine and saving on fuel

You are right in the thinking of using less gas and that's exactly what the purpose was to have the start/stop feature. The main goal of doing it (at least here in the States) is for zero fuel ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
24 votes
Accepted

Are trims (Hubcaps) on a car tires necessary?

No, hubcaps are purely cosmetic and do not need to be fitted. Some designs improve fuel economy and reduce wind noise by having a fairly flat surface but a car with one or more missing hubcaps is ...
Steve Matthews's user avatar
24 votes

If I am just replacing the car engine, do I need to replace the odometer as well?

I've never replaced an odometer when replacing an engine. What I will do, however, is make a note in the cars documentation that the engine was replaced at xxx,000 miles with a new/refurbished engine ...
PeteCon's user avatar
  • 8,712
21 votes
Accepted

How slow ( not zero) can a car engine run without hurting engine and saving on fuel

The oil problem You can run any engine speed you want as long as you keep the oil pressure up. Because of the impossibility of getting a roller bearing down a crankshaft, engine bearings are "...
Harper - Reinstate Monica's user avatar
21 votes

jacking up a car on "grass paving block" - how to secure jack and supports?

I typically use a piece of solid wood large enough to completely fit under the jackstand. Here in the States it would most likely be a piece of 2"x8" or 2"x10" board. I don't know ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
18 votes

Driving on full tank

No. Vehicle weight is only one factor of fuel economy. The most important factor is air resistance. Vehicle weight comes as the second most important factor. My ~1700 kg (car + driver) Toyota RAV4 ...
juhist's user avatar
  • 14.7k
18 votes

Why don't I get shocked constantly?

Unless you touch both battery posts, your body isn't completing the circuit from - to + The voltage is not high enough to overcome the resistance of your body (under most circumstances) The most ...
raydowe's user avatar
  • 3,012
16 votes
Accepted

What happens when I shift gears without pressing the clutch in a manual transmission while the car is running?

It is not a good idea to change gear without using the clutch, you will cause unnecessary wear that will end up causing an expensive bill. When you select a gear, there is a component in the gearbox ...
HandyHowie's user avatar
  • 25.5k
15 votes
Accepted

Why do car starter motors draw so much current?

It takes a LOT of power to get the rotating assembly - crank, pistons (or rotors), etc. - moving. For reference, try turning your engine over with a breaker bar on the crank. It's not super-easy (...
3Dave's user avatar
  • 3,159
14 votes

How do I put my automatic car into neutral while moving in drive?

You can put your car into neutral by moving the gear selector into the position marked "N".
WeakMech's user avatar
  • 964
14 votes

Why do you use the "park" gear to park a car and not only the handbrake?

Putting the transmission into "Park" engages the "parking pawl" - essentially a metal pin that locks the output shaft of transmission (and thus the driven wheels) in place. As to why it exists - it ...
motosubatsu's user avatar
  • 10.3k
13 votes
Accepted

Brake have failed. Alternative means of braking

No. For (at least) three reasons: It's not safe. You're using the transmission/clutch to slow the vehicle down in a manner it wasn't designed to do. You're destroying your clutch. You state you ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
13 votes

If I am just replacing the car engine, do I need to replace the odometer as well?

You're probably better off not replacing the odometer. You will need to keep accurate track of how far the car has been driven in total, so if you were to later sell your car without disclosing that ...
Nuclear Hoagie's user avatar
12 votes

Can cats leave scratch marks on cars?

It's hard to be sure, but that looks like single-stage paint (without a hard-wearing clearcoat). If so, it is relatively soft paint that could easily be scratched. Judging by the angle of attack (and ...
Zaid's user avatar
  • 39.2k
12 votes

Are car batteries meant to be disposable or are they re-chargeable?

As Steve has explained, the battery is rechargable and is constantly charged and discharged when it's in use. This process of charging and discharging is not perfect. Over time, the components in ...
Hobbes's user avatar
  • 4,412
12 votes

AC Delco | Should this be worrying me? The battery is just 9 months old

It looks to me as the battery has been boiled, meaning the alternator overcharged it. This has several implications: If the alternator overcharged it, then it will do so again. If this is the case, ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
11 votes

Can cats leave scratch marks on cars?

My experience with cats is that they do enjoy sticking their claws into something soft to sharpen them. Cats will completely destroy furniture this way. The scratches you are showing are on hard metal ...
tlhIngan's user avatar
  • 12.2k
10 votes
Accepted

How to setup the car so that while driving I do not have mist glass?

In the two pictures/icons you provide the arrow is intended to indicate the flow of air with regards to the cabin. Where the arrow is coming in from outside the car allows air from outside the vehicle ...
motosubatsu's user avatar
  • 10.3k
9 votes

What is the purpose of a microphone placed at rear view mirror?

GM vehicles often came standard with OnStar, GM's roadside assistance system. 2005 may be a little early for factory-installed Bluetooth.
tlhIngan's user avatar
  • 12.2k
9 votes

Why do car starter motors draw so much current?

A characteristic of electric motors is that they produce the highest torque when stationary, coupled to this is a very high initial current 400 to 600A for cars and commercial starter motors can ...
Solar Mike's user avatar
  • 34.7k
8 votes
Accepted

OBD-II difference between signal ground and chassis ground

You are over thinking things, just connect your devices (OBD & Pi) to a good chassis ground: The difference between chassis and signal ground is: Chassis Ground Pin 4: Is exactly that, ...
Newbie Noob's user avatar
  • 2,780
8 votes
Accepted

Why don't cars have multiple disk clutches as motorcycles do?

It all comes down to size. There is one thing which makes a clutch work, whether wet or dry. It comes down to friction. There are two ways to achieve the friction needed to transfer the energy from ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
8 votes

How slow ( not zero) can a car engine run without hurting engine and saving on fuel

The engine needs a minimum rpm to idle smoothly - a v8 can idle smoothly about 500to 600rpm but a 1 litre 3 cylinder needs around 700 to 900rpm... It is not the companies that really decided to do ...
Solar Mike's user avatar
  • 34.7k
8 votes

jacking up a car on "grass paving block" - how to secure jack and supports?

Your problem is a dangerous one. I am very strict with jackstand safety because I'm old and have seen too much. Plywood is definitely out. 2X12 are better, but any give in the soil beneath can cause ...
Jupiter's user avatar
  • 3,420
7 votes
Accepted

tires with TPMS. Why do they behave like this?

Every TPMS system is different. The one thing they have in common is that per government the sensors must last a minimum of 10 years (it's funny I know). To accomplish this feat running on batteries ...
vini_i's user avatar
  • 16k

Only top scored, non community-wiki answers of a minimum length are eligible