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

Questions tagged [exhaust]

Questions about Exhaust systems, Catalytic Converters and Headers/Manifolds

A set of hollow tubes or pipes that burnt fuel gasses flow into on an internal combustion engine. The exhaust system can be comprised of an exhaust manifold, catalytic converter, header pipe and muffler as well as house various sensors.

Image of an exhaust system for an automobile

enter image description here

359 questions
38
votes
3 answers

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 local workshops; they say, and I quote, "The car…
Sandman
  • 685
  • 4
  • 8
  • 11
32
votes
7 answers

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 disadvantages of the current design: The expense of…
George
  • 6,605
  • 38
  • 86
  • 123
31
votes
2 answers

Why do two-stroke engine exhaust pipes look so strange?

Two stroke gasoline engine exhaust pipes are shaped strange. They expand into a wide diameter and then shrink down to a very small diameter where the exhaust gasses emerge into the environment. - Why are they shaped in such a strange way? - What is…
DucatiKiller
  • 32,976
  • 22
  • 150
  • 267
26
votes
12 answers

What is the best way to remove a stuck/rusted exhaust bolt?

I'm trying to disassemble the exhaust system on a 2000-2003 Nissan Maxima and I'm having trouble removing one last bolt. It's got a 14mm head and its just plain STUCK. I've tried soaking it overnight with PB Blaster, then the next morning I tried…
NoCarrier
  • 2,902
  • 4
  • 25
  • 21
21
votes
1 answer

What does pie cut exhaust mean?

As the title says, when looking at building a custom exhaust system I've heard the reference called pie cut exhaust but I was unable to find any definition or terminology so I was curious to know what does it mean?
Hᴇʀʙɪᴇ
  • 3,737
  • 8
  • 36
  • 67
19
votes
1 answer

Is this what is making my car sound like a racecar?

Recently, my car (2000 Mercury Grand Marquis) started sounding like a racecar: the engine became very loud. There's clearly something going wrong with the exhaust system. I'm trying to understand the problem. I took a peek under the car, and I…
cheeken
  • 293
  • 1
  • 2
  • 6
16
votes
5 answers

When car is standing still, I smell Diesel exhaust. Why?

In my 2003 Opel Vectra, the cabin air smells of Diesel exhaust while stopped at e.g. a red light. The exhaust smell goes away when driving, and it also doesn't come back if I turn the ventilation off before stopping at a light. It's not…
Torben Gundtofte-Bruun
  • 891
  • 4
  • 10
  • 18
16
votes
3 answers

How can I tell if I have bad cats?

No, not that cat! Catalytic converters - or "cats" - have a nasty habit of failing with age. What are the symptoms associated with a cat that's gone bad? Are there any tests that could definitively confirm that a cat has gone bad?
Zaid
  • 39,276
  • 50
  • 151
  • 294
16
votes
2 answers

Should motorcyle exhaust headers ever glow red hot

I've got a '99 Pegaso 650 which hasn't been running for about 7 years. It's was in a quite a deteriorated state when I got it, i.e. seized carbs, tank full of water, sump full of an ugly fuel/oil mix, I seriously I drained about 5 liters from…
Ian Oakes
  • 668
  • 3
  • 8
  • 20
13
votes
7 answers

Why have I had to replace so many exhaust pipes?

My largest car maintenance cost is exhaust pipes, mostly catalytic converters. I do not think this is the case for most people. What am I doing wrong? I tend to buy cheap cars (<£500), change the oil myself, get the brakes changed when they squeak…
User65535
  • 505
  • 5
  • 13
13
votes
4 answers

What is this yellow powder on my exhaust manifold?

I took off the heat shield from the exhaust manifold on my 2003 Nissan Primera while looking for an exhaust leak, and I noticed this yellowish poweder / dust on it: Any ideas what it is? EDIT Sept. 19th 2017 So I wiped a section of the yellow…
Robert S. Barnes
  • 15,780
  • 72
  • 157
  • 249
13
votes
2 answers

How does condensed water get sent out of an exhaust system?

We've all seen water dribbling out a car exhaust when we're following someone accelerating out of a stoplight. I know that the water is an inevitable product of combustion, but I find myself wondering how the liquid gets out of the exhaust…
Daniel Griscom
  • 918
  • 4
  • 12
  • 27
13
votes
1 answer

What are the pro's and con's of compression braking vs. exhaust braking?

My truck supports 2 types of engine brakes: Compression release brake Exhaust brake Both can be selectively deactivated using switches. What are the pro's and con's of each type of engine braking system? (considering various factors like component…
niko
  • 343
  • 2
  • 10
12
votes
1 answer

What are the tell tale signs of a catalytic converter that might be going bad?

I've owned two vehicles whose catalytic converters were recalled due two a couple of reasons: one being the quality of the CC and the other being a reduction in power due to a material building up and reducing airflow. The car I own now (2007…
Cᴏʀʏ
  • 1,190
  • 12
  • 16
12
votes
4 answers

Is it possible for a vehicle to be manufactured without a catalytic converter?

Can a new vehicle from a plant be produced without a catalytic converter? Is it possible? I am a lecturer at a college in Zimbabwe, and my students recently asked this question, so I am researching.
Charly K Mwamber
  • 121
  • 1
  • 3
1
2 3
…
23 24