The point at which air enters the intake tract of a motor vehicle or stationary engine

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6answers
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When is a cold air intake system beneficial?

Cold air intake must be one of the popular mods there is, and one subject to the most controversy as well. Manufacturers of such systems advertise 5-20 HP gains, yet there are claims that this mod ...
15
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6answers
2k views

Why or why not increase engine efficiency by running the car “fuel-lean” (using a turbo or supercharger)?

Everyone wants their cars to use less fuel, right? I read the following passage about running the car fuel lean from this website: Run the engine fuel-lean, that is, use excess air. It is well ...
12
votes
3answers
1k views

Cold air intake causing rich condition

This is a follow up question to my initial question which can be found here : LTFT and STFT values are off and don't make sense Car is a 2015 F10 M5 Mods : Cold air intake, aftermarket rear ...
12
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2answers
332 views

Yamaha R1 intake tract configuration

Interesting Configuration The Yamaha R1 has a very strange intake design. Notice the intake horns in the image below. They sit above the throttle bodies and are not attached directly to them ...
11
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4answers
347 views

Cold Air Intake and Engine Wear

I'm contemplating whether or not to retrofit my car with a cold-air intake and performance air filter. Will doing so lower the lifespan of my engine? That is to say, increase likelihood of engine ...
10
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2answers
2k views

How do variable-length intake manifolds work?

I have heard many vehicle manufacturers have been using this to improve power and torque figures. They do this by altering the length of the manifold, I am hoping for better diagrammatic explanation.
10
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2answers
112 views

Why Have More Than One IAC Type Device On an Engine?

I've had two Mazda's, a 97 323 and 98 626. On both these car's engines there was only a single IAC mounted on top of the throttle body, and no other device for adding air flow on the intake side. ...
9
votes
2answers
3k views

What is the difference between a MAP and a MAF sensor

Generally a car uses either MAP or MAF to determine the air flow index the engine is getting and that older cars used to have MAP and newer ones often use MAF and cars like the Mitsubishi EVO uses ...
8
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1answer
86 views

Is it possible to extend the length of the shaft on an existing turbocharger, further distancing the compressor from the turbine?

I'm toying with turbojet engine ideas, and over the course of my research it occurred to me that the combustion chamber could be more power-efficient and space-efficient if it was aligned in the ...
7
votes
3answers
10k views

What are the pros and cons of installing an filter on a bike?

What are the advantages and disadvantages of installing high performance air filters (K&N,Green cotton,etc.) over original filter? What are the changes/working occur internally?
7
votes
1answer
68 views

Dirty air filter seal

Whenever I have had work done in the past that I can't perform myself, timing belt etc every garage I have been too has made a real mess with my air filter. When I check the filter there is always ...
6
votes
4answers
309 views

Do air filters purifty air better with age?

I have been reading in a few places that air filters get better with age, is this true? And how much better? Would it have any effect on quality of the oil or make oil dirty faster? Or is there ...
6
votes
3answers
934 views

After Replacing EGR valve and tube: repeat of code P0401 for 98 Accord V6

About 13 months and 7500 miles ago, my mechanic replaced the EGR Valve and Tube and cleaned the intake to solve the low airflow problem. Now I'm again getting an insufficient flow warning with my ...
6
votes
1answer
471 views

Oily Sludge in the Intake Manifold

When taking off the throttle body to clean my IAC, I noticed that there was a thick layer of oily sludge coating pretty much everything inside the intake manifold: I have two queastions: How did ...
6
votes
1answer
3k views

How to access the Idle Air Control Valve, Renault Clio mk2

I have an idling issue with my Renault Clio mk2 1.2L 2002 - the engine stalls as I slow down at lights and roundabouts etc... I have been searching the web for solutions to this problem, Most answers ...
5
votes
4answers
297 views

Can 100% calculated load be reached in neutral?

While searching for information about how is engine load calculated I came across this question which contains an equation for the ECU load calculations. As I understand it under fixed atmospheric ...
5
votes
2answers
367 views

Why do most mass-production motorcycles have their intakes facing backwards?

Almost every motorcycle I have seen has its air intake mounted such that it is sucking in air from the direction opposing travel. According to fluid dynamics, if the intake is made to face forwards, ...
5
votes
2answers
4k views

Honda S2000 with cold air intake; rain driving

I recently purchased a cold air intake kit from Injen (SP1305P, seen below) at the recommendation of my mechanic and am planning on installing it in my 2001 Honda S2000. However, it is my daily driver,...
5
votes
2answers
3k views

Effects of driving through deep water WITHOUT hydrolocking (car still bogged down and died)

So, yesterday we had very heavy rains, and unfortunately I was driving in an unfamiliar area of town. I drove through high water, which caused my car to sputter and so I turned around. The car behaved ...
5
votes
2answers
103 views

How much horsepower to expect from a cold air intake in Dodge Ram

It's a 1999 Dodge Ram 1500 4x4, Laramie SLT, automatic transmission, 5.9l magnum engine, and crew cab (222k mi). I have a friend who could put a cold air intake on it, with a new hood. But I have ...
5
votes
2answers
1k views

1993 Jeep stalls on acceleration, floods, hard to start

My 1993 Jeep Wrangler has about 200,000 miles, in good shape. It usually starts right up, but it's started intermittently flooding, so that I have to crank and crank with the accelerator all the way ...
5
votes
1answer
93 views

Where does the Toyota Vitz air intake take air from?

I am just curious where my engine air filter is taking air from. Below is a picture of my car's (Toyota Vitz 2007) engine (not a picture of my exact engine). As I can see, the air filter should ...
5
votes
1answer
12k views

1991 Chevrolet S10 - Sputtering, hiccups, stalling, bad acceleration

I'm having a problem with my pickup; It's a 1991 Chevy S10, 2WD P/U, 2.5L I4 engine with around 185,000 miles on it. It's the Iron Duke engine, a throttle body injection motor. I'm not a mechanic, ...
5
votes
1answer
3k views

How to clean the MAF sensor on a 1997 Nissan Altima?

I have a 1997 Nissan Altima sedan. I’ve been told the issues I’m having with my car is from the mass air flow sensor. I was wondering how to clean/repair this sensor and contact points the best? What ...
4
votes
1answer
122 views

Oiling lawn mower air filters

Why does the air filter on a lawn mower need to be oiled? Is it true that major engine damage will occur if the intake air filter is not oiled?
4
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1answer
4k views

High pitch whistle at a very particular throttle level

The symptom: while accelerating, at a very particular throttle level/pedal angle my engine recently started whistling in a very high pitch. If I let go of the gas or push it in more the sound goes ...
3
votes
1answer
251 views

Found a lizard in my car, I have not driven it for 20 or more days

I went on a vacation for three weeks. When I came back and opened my car, I found a lizard in the car. I have had the air re-circulating knob set to ON. I am still guessing how this lizard entered my ...
3
votes
1answer
135 views

2002 Honda Civic Si Air Box

I am about to replace a cracked air box on my 2002 Honda Civic Si. The one question I have is how do I get the old air box bolts out of the old air box top half and into the new one since it did not ...
3
votes
1answer
2k views

Clearing a P0507 on a Dodge Stratus

My 06 Dodge Stratus (4 cylender) is showing a P0507 off of the Torque app. My idle is sitting at near 1100 rpm versus the standard 800. I read up on the code and started looking for a vaccum leak ...
3
votes
1answer
31 views

after replacing icv,intake boot,valve cover gasket and return to stock air box from CAI,car will not hold idle 325i 1994

Car will not idle after re-installing stock air box from previous cold air intake. I replaced idle control valve also replaced intake boot as well as valve cover gasket along with spark plugs, BMW ...
2
votes
1answer
62 views

KTM Duke 200, Broken Airbox

My duke generates an odd noise and when I looked under my seat what I saw was an open air filter box because of the broken screws. When I took my bike to the service center what they told was to ...
2
votes
1answer
131 views

Why is this hollow plastic piece attached to the Karizma's air intake?

I was helping my cousin with a motorcycle teardown a while back (planning for a café racer build) and was puzzled by something on his '07 Karizma. The red arrow in the picture above points to a ...
2
votes
1answer
473 views

Throttle randomly gets stuck in closed position

I recently did some work on my throttle body (had it removed, cleaned all the valves, etc.) and after I put it back together I noticed something strange. Every once in a while, after the car has been ...
2
votes
1answer
301 views

roots blower pressure on Detroit 2 cycle Diesel 371 cubic inches

I need the blower pressure for a Detroit 2 cycle Diesel 371 cubic inch Oliver 99 tractor
2
votes
1answer
666 views

Toyota Avensis Intake Manifold Rattle Fix - quesion about gasket

I have a Toyota Avensis which has the intake manifold rattle problem. I asked the dealer for a price on the new part and he quoted me €400. From a breakers yard they are hard to get and the going rate ...
2
votes
1answer
63 views

1991 BMW E30 - knocking when put into 1st

I knew I had a minor vacuum leak, but it got worse all of sudden while at a stoplight. In trying to get through to the next block, the engine started to knock. (My guess is preignition thanks to the ...
1
vote
2answers
4k views

What is an oil catch can for?

Some RX-8 owners have been recommending installing an oil catch can, to prevent problems from "overfilling" the oil. I assume this doesn't mean spillover (does it?), but instead, too much oil in the ...
1
vote
1answer
65 views

Is this PCV hose broken?

I asked a question earlier about a P0171 MIL in my 2007 toyota corolla. The question is here: Diagnosing P0171 2007 Toyota Corolla I only have a OBD2 reader, I just bought a scanner, which should come ...
1
vote
1answer
77 views

ATV engine does not start well

I have a chinese ATV with an engine copied from an ~2006 Honda Foreman 400 (a very simple 1 cylinder 400cc carburetor based engine). It's an exact copy with regards to parts. However it does not start ...
1
vote
1answer
66 views

Cleaning Admission

I cleaned the air intake spraying a Sonax liquid air intake cleaner. I took off the air filter, sprayed, waited to get dry and started the engine. It works well in my car that I think it was clean ...