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Old 4th July 2017, 21:09   #16
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Default Re: Explained: Why Diesel engines need a throttle body & throttle plate

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Originally Posted by Jeroen View Post
Maybe semantics?
Guess it is semantics.
In your mind what do you think is meant by 'fueling system'?

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Originally Posted by dracul View Post
IIRC, Matador have a throttle plate
Right. And nothing to do with emissions.

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Old 4th July 2017, 21:21   #17
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Default Re: Explained: Why Diesel engines need a throttle body & throttle plate

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Originally Posted by Sutripta View Post
Guess it is semantics.
In your mind what do you think is meant by 'fueling system'?
I would think bits like the injectors, the fuel lines, the filters, the various pumps etc. If there is a mechanical governor that would be included as well.

But everything to do with electronics or to be more precise computers, I would not necessarily include in the term fuelling system.

I think of ECU and or other computer boxes as seperate systems controlling other systems. Along this analogy, if talking about external and internal lighting system I would not include the BCM or whatever box controls that.

Same for the transmission/gearing system.

My thinking is probably unconscious biased based on workshop manuals and part catalogues which often follow a similar approach.

Jeroen
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Old 4th July 2017, 21:31   #18
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Default Re: Explained: Why Diesel engines need a throttle body & throttle plate

^^^
Functionally why should one differentiate between a mechanical governor and an electronic one (or hydraulic or pneumatic for that matter)?

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Old 4th July 2017, 22:08   #19
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Default Re: Explained: Why Diesel engines need a throttle body & throttle plate

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Originally Posted by Sutripta View Post
Right. And nothing to do with emissions.

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Yes. No one was concerned about emissions then.
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Old 5th July 2017, 09:26   #20
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Default Re: Explained: Why Diesel engines need a throttle body & throttle plate

Quoting my original post.
Quote:
Originally Posted by Sankar View Post
Then why does some Diesel engines come equipped with a throttle body
Yes some modern engines have throttle bodies and some do not. The primary reason for its presence is emissions control and Exhaust Gas Recirculation (EGR). The ECU by means of electrical motor or solenoid controlled vacuum line can control the actuation of the butterfly valve in the throttle body to restrict the amount of fresh air (from turbo charger) into the intake manifold under low engine load situations. This helps create a pressure differential and thus helps the EGR system to feed more exhaust into the intake manifold.
Found the relevant section from Denso on their public domain so that i can share it here. Crysta engine management and components are by Denso.

Explained: Why Diesel engines need a throttle body & throttle plate-denso.jpg

Just to clarify that I am not letting my imagination run wild.

Last edited by Sankar : 5th July 2017 at 09:29.
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Old 7th July 2017, 20:55   #21
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Default Re: Explained: Why Diesel engines need a throttle body & throttle plate

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Originally Posted by Sutripta View Post
^^^
Functionally why should one differentiate between a mechanical governor and an electronic one (or hydraulic or pneumatic for that matter)?
At an abstract straightforward functional level it probably doesnít make a lot of difference, if any. In practice what you might want to add into such description, diagram, drawing and such would be very different.

A typical old School Mechanical governor (E.g Woodward on a marine diesel) would have four dials and one input lever. The position of the lever would more or less determine how much fuel was injected, so it controls RPM and or Loading depending on the application.

On the ocean going tugs I used to sail on that lever was moved through a fairly complex pneumatic/mechanical system. These tugs have controllable pitch propellors and are normally operated via a combined pitch/RPM lever on the bridge. It uses cleverly positioned cams that move pneumatic valves in a certain sequence and fashion. In addition there was a back up system where pitch and RPM are set independently from each other through separate levers/buttons and separate valves and actuators towards the Governor input lever.

So in the above system the actual fuel control functions are part of the Governor itself (itís internal control system) and the pneumatic/mechanical components of the bridge lever (telegraph)

Would we consider such complex pneumatic/mechanical system part of the fuel system and or the governor?

Itís probably anybodies guess and I donít think there is a right or wrong answer.

But here is how it shows up in the ships manual:

The engine manual (Werkspoor) would show the fuel injectors, injection pumps and all filters, pipes, valves on the engine. It would also show the Governor.

There would be a separate Woodward manual and there would be a separate manual for the pneumatic/mechanical control system, courtesy of Lips.

If anything with electronics all the control functions move into one box! Just the various inputs (mostly sensors) and outputs (various actuators, valves etc) will be spread all over the place.

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Old 7th July 2017, 21:06   #22
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Default Re: Explained: Why Diesel engines need a throttle body & throttle plate

Any component/ module/ subsystem which directly affects fuel delivery to an engine is, IMO, part of the fueling system.

eg. When engines show instability/ rough running (esp true of single cylinders trying to pick up rpm after an overrun), we call it a fueling issue, not an ECU issue.

Different manuals would have more to do with serviceability as seen by the subsystem manufacturer.

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Old 8th July 2017, 10:18   #23
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Default Re: Explained: Why Diesel engines need a throttle body & throttle plate

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Originally Posted by Sutripta View Post
Any component/ module/ subsystem which directly affects fuel delivery to an engine is, IMO, part of the fueling system.
On modern cars the state of the battery can cause all sorts of instability on the engine. Same is true for say corrosion in electrical connections. Along this logic would you consider the power supply and electrical system part of the feeling system.

On my Jaguar a well known problem causes the engine to go into limp home mode. This is often caused by one of the microswitches on the brake pedal that is an input to the cruise control. Wonky switch causes it to go into limp home mode. It even has its own P-code. Is the brake part of the feeling system.


Quote:
Originally Posted by Sutripta View Post
eg. When engines show instability/ rough running (esp true of single cylinders trying to pick up rpm after an overrun), we call it a fueling issue, not an ECU issue.
Maybe thatís why I get drawn into so many discussions on the forum. I call a engine running rough nothing but an engine running rough, until I know what causes it.

Again, I think itís down to semantics and or customs. Not necessarily (engineering) logic.

Jeroen
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Old 8th July 2017, 21:03   #24
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Default Re: Explained: Why Diesel engines need a throttle body & throttle plate

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Originally Posted by Jeroen View Post
Would we consider such complex pneumatic/mechanical system part of the fuel system and or the governor?
I consider all governors part of the fueling system. You don't. To you mechanical governors are part of the fueling system, electronic ones aren't.
If you could explain clearly your rationale for this, in clear language a layman can understand, I'd be enlightened. Your post describes some systems, but to my mind and understanding, does not answer this question.

Quote:
On modern cars the state of the battery can cause all sorts of instability on the engine.
True, and entirely unhelpful for this discussion!
Very clever, I might add.

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Old 9th July 2017, 08:59   #25
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Default Re: Explained: Why Diesel engines need a throttle body & throttle plate

The state of the battery, if it falls below the threshold voltage could create minor issues, nothing that one cannot drive around with.

And in such cars, the limp home mode triggers in to save any further complications

Interesting thread..
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Old 9th July 2017, 11:57   #26
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Default Re: Explained: Why Diesel engines need a throttle body & throttle plate

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Originally Posted by Sutripta View Post
I consider all governors part of the fueling system. You don't. To you mechanical governors are part of the fueling system, electronic ones aren't.
If you could explain clearly your rationale for this, in clear language a layman can understand, I'd be enlightened. Your post describes some systems, but to my mind and understanding, does not answer this question.


True, and entirely unhelpful for this discussion!
Very clever, I might add.
Whatever term you use to define something, it also comes with an understanding what is included and what not. According to your definition:

Quote:
Any component/ module/ subsystem which directly affects fuel delivery to an engine is, IMO, part of the fueling system.
But then how far do you take it? Apparently the cruise control isn’t given your feedback.

So let’s explore the boundaries of what is and isn’t contained in a fuelling system. Hopefully that will show you why I look at a governor somewhat differently.

A few examples that all affect the running of an engine;

My Jaguar has a so called “Running Loss System”. Some other manufacturers might call it differently. In essence the venting/pressure of the fuel tank is controlled by means of various valves, lots of plumbing, so called EVPA canisters (i.e. charcoal filters). It’s actually a pretty complex bit of kit. And it’s directly hooked up to the fuel tank. Now on a petrol car it's a bit different then on a diesel. But still in both cases it can affect the running of an engine.

Is it part of the fuelling system?

We probably both agree that the fuel pump is part of the fuelling system. But what about the relais that controls that pump. And that relais is subsequently controlled by the ECU or similar.

Does the fuelling system end at the electrical connector on the fuel pomp?

What about an inertia switch. It’s main function is to stop the engine in case of a crash. Depends a bit per manufacturer, but usually it trips the fuel pump relay and or electrical supply and these days calls the emergency services.

So with the term fuelling system we need to determine what is part of it. Different parts, different functions. And of course, these days, parts on cars could have multiple functions affecting different systems. E.g. the inertia switch that could trip three different actions, stop fuel, stop electrical supply, call 911.

So I start clustering bits and pieces and I tend to look at it at what is often referred to as a horizontal layered model. In the Telecom world sometimes referred to as the Hamburger model. The various layers have distinct interfaces and way of interacting with one another. could be mechanical, pneumatically, electrically, digital etc.

So here goes:

Layer 1 is all the ‘hard’ physical bits, e.g. pipes, tubing, valves, pumps, injectors,
Layer 2 is all sensors and actuators. e.g. temperature, pressure, flow sensors etc
Layer 3 is all electrical systems. e.g. wiring loom, fuses, connectors, relays etc
Layer 4 is the control layer, e.g. the various ECU, PCM, TCM etc.

Depending on your preferences, complexity of the systems at hand you might see a few more layers. A pneumatic system could sit in layer 3 and or 4.

A governor is essentially a PID controller. However, a mechanical governor for me is just a self contained metal box with usually just a few (mechanical) inputs. That’s why I put it in layer 1. You could argue some of the bits of a mechanical governor are part of layer 2 and 4. To me that isn’t useful. I think overall it fits in well in layer 1. It also needs to sit right on top of the engine.

Simply put, a mechanical governor for me is a simple physical item, similar like a fuel pump, a fuel filter, separator.

An electronic governor could sit, physically, anywhere obviously. But it can be part of an “electronic” box having a multitude of in- and output for various systems and it interacts, usually electronically/digitally with multiple function and systems. E.g. the cruise control system.

Such a layered approach works well on other system as well. E.g. brake system, drivetrain etc.

But as I said before, at the end of the day I think it is down to semantics, custom or certain conventions. Whatever you prefer / find more logical / natural


Quote:
Originally Posted by headers View Post
The state of the battery, if it falls below the threshold voltage could create minor issues, nothing that one cannot drive around with.

And in such cars, the limp home mode triggers in to save any further complications
.
Low battery voltage can create all sorts of minor issues up to major issues, such as not starting. Although they could be minor, in many cases they are quite a bit more than that. There are various threads on the forums with car owners posting a host of issues that were related to low voltage. To my earlier comment. It’s not just low voltage. The same sort of issues can pop up due to poor connection. As cars get older you will see, over time, connectors, fuses and such corrode. That creates higher resistance, which cause a voltage drop across that component, which mean lower voltage for the rest of the car. So you see similar problems. But battery voltage and charge state is very easy to check.

Many low voltage problems can be identified by using a proper OBD scanner. There are many codes for various low voltage conditions across many different components. Trouble shooting what causes that low voltage can be tricky sometimes.

The limp home or whatever it happens to be called on a particular car can be triggered by various low voltage situations, or not, or a whole host of different reasons. In my Jaguar the actual term shown on the display is Fail Safe Mode. And there is no way it gets you home. The car does less then a crawl in that state.

Jeroen

Last edited by Jeroen : 9th July 2017 at 12:06.
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Old 9th July 2017, 22:15   #27
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Default Re: Explained: Why Diesel engines need a throttle body & throttle plate

S-Cross 1.6 : Throttle plate delete done by Blackworks

Inspired by my mod Guruji : Sankar, I too got the throttle plate removed

Blackworks did the job and it took hardly 15 minutes. The plate is open by default when engine is off. Also the mod is reversible in S-Cross 1.6. Blackworks just removed the throttle plate and left the shaft as it is.

Impressions (after driving 150 KM)

1. Engine is more free revving and I can feel the raw power

2. When I switch off the engine, there is some mild shudder which was not present before.
Attached Thumbnails
Explained: Why Diesel engines need a throttle body & throttle plate-img20170709wa0050.jpg  

Explained: Why Diesel engines need a throttle body & throttle plate-img20170709wa0048.jpg  

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Old 9th July 2017, 23:38   #28
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Default Re: Explained: Why Diesel engines need a throttle body & throttle plate

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Originally Posted by Dr.Naren View Post

Impressions (after driving 150 KM)

1. Engine is more free revving and I can feel the raw power

2. When I switch off the engine, there is some mild shudder which was not present before.
Good The throttle response gets slightly better.
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Old 10th July 2017, 17:15   #29
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Default Re: Explained: Why Diesel engines need a throttle body & throttle plate

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Good The throttle response gets slightly better.
I did couple of 0-100 runs post TB plate delete. The results were consistent. I have gained around 0.6 seconds .

Details here :
http://www.team-bhp.com/forum/modifi...ml#post4231742 (S-Cross 1.6L : Wolf Moto Remap!)
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Old 10th July 2017, 18:44   #30
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Default Re: Explained: Why Diesel engines need a throttle body & throttle plate

any idea what happens to fuel efficiency and emissions?

I donít think you would be allowed to do such modifications in most of Europe, but it is certainly an interesting experiment!

Jeroen
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