Motor Vehicle Maintenance & Repair Stack Exchange
Motor Vehicle Maintenance & Repair Stack Exchange

Most Popular

more tags
1500 questions
17
votes
3 answers

How is "outside temperature" measured in a car?

Most cars have a display for outside temperature, and I have been wondering how it was measured... In other words, where exactly is the sensor and how reliable is it?
Mehper C. Palavuzlar
  • 271
  • 1
  • 2
  • 5
17
votes
3 answers

Is my head gasket cracked?

My wife hit a large puddle of water in her 2006 Mazda 5. Until then it was running fine. The check engine light came on and car shut down and would not start again. Mazda says it is a head gasket. Is that possible?
user25269
  • 171
  • 1
  • 3
17
votes
2 answers

What is crankshaft grinding and why is it done?

I saw a lot of YouTube videos referring to crankshaft grinding, while watching videos about working on crankshafts. I don't understand what crankshaft grinding does. If we grind a crankshaft, then how does it stay compatible with the vehicle where…
Inquisitive
  • 273
  • 1
  • 3
  • 8
17
votes
9 answers

Why don't some modern cars automatically turn off headlights when stopped?

I forgot the lights on overnight on a 2016 Volkswagen Jetta and 16 hours later when I came back to the car the lights were still on but the car wouldn't start. Can't the car check the battery level and automatically turn off lights if it had been…
Dan Dascalescu
  • 381
  • 1
  • 3
  • 9
17
votes
10 answers

How can I remove a seized brake disc?

I'm changing the rear brake discs and pads on my Ford Focus C-MAX. I've done one side which was fairly easy, but on the other side I can't get the disc off. There is nothing holding it on as far as I can see but it won't budge. I can't pull it too…
BG100
  • 538
  • 1
  • 6
  • 11
17
votes
4 answers

How are rotary valves sealed

I have been looking for information on how rotary valves are sealed, but have not had much luck. Coates has engines with them, and they are oil less to boot or so they claim, but how do you get them to seal during a compression stroke? The only…
Cc Dd
  • 2,879
  • 2
  • 13
  • 31
17
votes
3 answers

Stainless Steel Fasteners

In the past 6-months or so, I purchased this set of stainless steel hex head bolt fasteners. In the kit, they require you to install the bolts using "anti-seize as a regular practice". The seller specifically states it is an "absolute requirement…
Pᴀᴜʟsᴛᴇʀ2
  • 165,084
  • 32
  • 259
  • 508
17
votes
4 answers

What iPhone/iPad app works best with ELM327 Bluetooth OBD-II reader?

I've found a number of apps for the iPhone/iPad that connect to ODB-II readers via WiFi, but unfortunately that means that it disables 3G and all the benefits of having a 3G device built into my dash. I can't seem to find any apps that work via…
Chase Florell
  • 311
  • 1
  • 2
  • 10
17
votes
2 answers

What happens to a car when it hasn't been driven for 12 years?

I'm hoping that I'll soon be the owner of 2l turbo charged, 4wd hatchback that's been sat in a garage, undriven for over a decade. Trouble is that I won't be able to give it a full inspection until I actually own it (long story!) From other…
BenLanc
  • 295
  • 1
  • 2
  • 8
17
votes
2 answers

Is there a rule of thumb for estimating volumetric efficiency?

Here's a situation I encounter quite often During diagnosis, I want to determine if the mass air flow sensor(s) [MAF(s)] is/are healthy. I hook up an OBDII reader to a vehicle that I'm trying to diagnose and get access to real-time mass air flow…
Zaid
  • 39,276
  • 50
  • 151
  • 294
17
votes
3 answers

Why is gas around a car battery only at risk of ignition from jumper cables?

As pointed out in Jump starting a dead battery: Connect black wire to negative pole of battery or grounded metal?, you connect the black jumper cable to the dead car's chassis to avoid sparks made during the connection near the battery, which could…
Bas
  • 407
  • 1
  • 5
  • 9
17
votes
5 answers

Smart and effective ways to light up a garage without relying on power outlets?

I am currently renting an garage in an underground parking lot. The garage has no light inside nor electric plugs. The only form of illumination available comes from the few neon lights in the corridor/driveway of the underground parking lot. What I…
JoErNanO
  • 1,765
  • 4
  • 23
  • 47
17
votes
4 answers

What does it mean to retard an engine?

I have come across this term. What does it mean to retard an engine? When would you typically have to do such a thing? What can happen if you don't or incorrectly retard the engine? What sort of vehicle or machine require engine retarding?
Jonathan Musso
  • 4,740
  • 11
  • 30
  • 52
17
votes
1 answer

Cleaning brake fluid (general tips)

There are some other threads on other websites about cleaning up brake fluid. But I just wanted to get a more organized, concise answer here on SE. Wanted to confirm that cleaning up brake fluid just requires water and the same detergent you would…
CarlGammaSagan
  • 559
  • 3
  • 6
  • 11
17
votes
2 answers

What mechanical revolution is measured in "RPM"?

I do realize that it stands for revolutions per minute, but what are the revolving pieces that are measured? Assuming it is the crankshaft, is RPM calculated by the crank shaft sensor, or by some other means? Why do some old, carbureted cars not…
method
  • 2,770
  • 12
  • 45
  • 61
1 2 3
…
99 100