40
votes
Is it possible for a vehicle to be manufactured without a catalytic converter?
You don't have to have an catalytic converter, they aren't required for the operation of an engine. Catalytic converters use chemical reactions to reduce the pollution in internal combustion engine ...
- 17.1k
29
votes
Accepted
Why have I had to replace so many exhaust pipes?
Another cause of rapid exhaust system rusting is driving patterns which don't warm up the vehicle thoroughly. In this case, a "thorough" warmup means the entire exhaust is hot enough to ...
- 3,667
23
votes
Accepted
What's the purpose of having the cat right after the exhaust manifold
The main purpose of putting it right after the manifold is heat. The cat functions best when hot. Placing it as close as possible to the manifold helps the cat heat faster and stay hotter, which ...
- 160k
22
votes
What does exhaust smell on oil and transmission dipstick mean?
First of all you're not smelling CO (carbon monoxide) as that is an odorless and colorless gas. What you are likely smelling are combustion byproducts and that is not at all uncommon in the engine ...
- 12.1k
21
votes
Accepted
How does condensed water get sent out of an exhaust system?
If there was ever that much water in the muffler such that it was sloshing around, it would be a sign of catastrophic failure in the engine, such as a blown head gasket and the "water" would actually ...
- 2,867
19
votes
Accepted
Is an exhaust pipe broken at engine connection fixable by a DIYer?
Can I just put the pipe back in and do something to seal them together again? Or do I need to replace that section of the exhaust pipe or the entire exhaust pipe?
You can attempt welding. It's not ...
- 798
17
votes
Accepted
How should I remove this corroded nut without rounding it?
The tool
Thanks to you all for your many good suggestions, but I thought I'd share how I actually got these nuts off today. First, more PB Blaster, and then while I was at the auto parts store ...
- 2,867
15
votes
Is it possible for a vehicle to be manufactured without a catalytic converter?
That will depend on the market regulations for the target country ie which country that vehicle will be sold in.
Cars built to be sold in Europe & US have to meet stringent regulations as regards ...
- 34.7k
14
votes
Accepted
What is this yellow powder on my exhaust manifold?
IMHO that powder is either:
Dust, that got "burned" by the hot exhaust manifold and transformed into some yellow-looking substance.
Sulfur, as the color has a striking resemblance to sulfur. The ...
- 8,488
13
votes
Is it possible for a vehicle to be manufactured without a catalytic converter?
Yes, in theory. The government doesn't care how your engine hits the required emissions numbers. As an engine designer, you get a tabula rasa, and are free to build any system that will do the job. ...
13
votes
Why have I had to replace so many exhaust pipes?
3 in 4 years?
That sounds like the engine mounts were loose or broken and putting undue strain on the pipe.
Another possibility is hitting the exhaust on sleeping policemen - are the roads in good ...
- 34.7k
12
votes
What is this yellow powder on my exhaust manifold?
If your engine was running / exhaust manifold hot; the yellow is then zinc oxide. It would result from a galvanized steel manifold which has naturally oxidized. At room temperature the ZnO is white , ...
- 3,688
10
votes
Accepted
How much room do I need to avoid carbon monoxide poisoning?
Is your Check Engine Light on?
That's a rhetorical question, what I mean to say is that if your ’04 Forester is in good tune, it really should not produce that much carbon monoxide.
Also, there are ...
- 12.4k
10
votes
How should I remove this corroded nut without rounding it?
A lot of localised heat to the nut will help.
A 1/2 inch spanner/wrench is slightly smaller than a 13mm, so that may still work after heating.
If you can’t get a splitter on it, you could drill a line ...
- 25.5k
9
votes
2004 Taurus - Help Identifying the leaking component
The left descending pipe is (or comes from) the exhaust manifold, and ends in a two-bolt flange. The flange bolts to a matching flange on the front end of the exhaust pipe, which runs aft from the ...
- 3,667
8
votes
Is it possible for a vehicle to be manufactured without a catalytic converter?
No Telsa has a cat. While you could bolt one to a Tesla it would serve no purpose.
- 311
8
votes
What does exhaust smell on oil and transmission dipstick mean?
Smelling AT fluid is (or did ) give a good hint of the transmission general condition , but it requires experience. The clutches and bands have material like brake pads and if they slip, they heat ...
- 3,688
8
votes
What does exhaust smell on oil and transmission dipstick mean?
If the motor oil has a distinct smell of exhaust fumes, it might also mean that the cylinder head gasket has become leaky. Transmission fluid should never smell of exhaust gases, but can get a certain ...
- 180
8
votes
How should I remove this corroded nut without rounding it?
As you don't care about saving the nut you have a few options. In addition to the good solutions mentioned in other answers I have a few suggestions:
One of the handiest tools out there is locking ...
- 17.1k
7
votes
Help me understand catalytic converters and exhaust restriction
Exhaust diameters don't work exactly like that. You may actually get better exhaust flow with a 2" pipe than a 2.25" pipe with some engines and some rpm.
The important thing is to balance flow ...
- 18.6k
7
votes
Accepted
Is it feasible to use the exhaust heat to warm the engine block?
The problem you'll have in extracting heat from your exhaust gases to heat your engine is twofold:
Gases don't generally have a high specific heat capacity so though it's hot, it's not a lot of heat ...
- 1,145
7
votes
Accepted
Why would a lighter flame go into an exhaust pipe?
This is a quick-n-dirty test done to see if there might be an issue with a burnt exhaust valve. Another similar test uses a dollar bill (or whatever currency you happen to have). What is being checked ...
- 160k
7
votes
How should I remove this corroded nut without rounding it?
As you've noted, you can't get a socket over the nut, which eliminates a large number of tools with sharp internals that resemble a socket.
Not many options remain, but one of them is a nut splitter.
...
- 4,915
7
votes
Why have I had to replace so many exhaust pipes?
For more than 25 years most auto exhaust systems have been 13 chrome stainless. I have never seen one corrode significantly; I have driven at lease 3 vehicles to about 130,000. So unless you are using ...
- 3,688
7
votes
Is an exhaust pipe broken at engine connection fixable by a DIYer?
If I were you, I'd try to take it back to the shop and tell them they busted the exhaust while replacing the transmission. It was working just fine before they touched it. You can see what they say, ...
- 160k
6
votes
What effect will replacing manifolds with headers have on oil temperature?
I would seriously look at improving your oil cooler.
I doubt going "larger" is the immediate solution, I'm betting it's the airflow across the heat exchanger. Relocate the cooler, modify/improve the ...
- 12.4k
6
votes
Accepted
How to fix broken exhaust pipe?
That exhaust looks well beyond the point of welding, even internally sleeving it would leave nothing around the outside to weld to.. I mean you could try gas welding it but to be honest I can't see ...
- 5,067
6
votes
Accepted
What socket fits the Catalytic-converter-to-Exhaust-manifold stud?
It's called a double D or shock absorber socket
- 1,392
5
votes
Accepted
Thick white (maybe blue) smoke from tailpipe while accelerating, then the smoke stopped and car runs normally
Per your edit, you said the mechanic replaced a PCV valve that was stuck open, causing the excessive smoking. PCV in this case stands for Positive Crankcase Ventilation. The valve is located on the ...
- 6,007
5
votes
Accepted
Help me understand catalytic converters and exhaust restriction
There's a huge amount of information you would need to know about your "theoretical car" before even a wild guess could be made.
As Rory mentioned, velocity is key. Sage old-school guys like Corky ...
- 12.4k
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