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Old 10th July 2017, 19:19   #31
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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
any idea what happens to fuel efficiency and emissions?
I have not noticed any significant difference in FE. My car is running with a decat downpipe and has passed Indian emission tests. I doubt TB plate delete would impact emissions by big margin. The engine is getting more fresh air now. Also the EGR is ON in my present map. I will get the EGR soft delete done as the TB plate is removed now

Quote:
I don’t think you would be allowed to do such modifications in most of Europe
Follow all the rules and there would not be any modifications-accessories thread in our forum . As per our law any modification is illegal. Between all these mods are very common in Europe : EGR delete, DPF delete, TB delete, Swirl flaps delete, decat downpipe etc etc. Spend some time on few International forums and I am sure you will find many.

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but it is certainly an interesting experiment!
Yes, it is!! Happy with the gains.

Cheers!

Last edited by Dr.Naren : 10th July 2017 at 19:22.
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Old 10th July 2017, 21:29   #32
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Default Re: Explained: Why Diesel engines need a throttle body & throttle plate

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Whatever term you use to define something, it also comes with an understanding what is included and what not. According to your definition:



But then how far do you take it? Apparently the cruise control isnít given your feedback.

So letís explore the boundaries of what is and isnít 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 ďRunning Loss SystemĒ. 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). Itís actually a pretty complex bit of kit. And itís 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. Itís 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 Ďhardí 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. Thatís 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 isnít 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 ďelectronicĒ 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




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. Itís 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
Lets agree to differ.

You are right in that I should refine my statement by saying that which directly affects fueling of a running fully operational engine, otherwise we'll soon land up with Exxon and Shell, let alone things like smart braking, or crash sensors. Exceptions. Next time I'll ask my friendly neighborhood lawyer to vet my posts for loopholes!

Models are used for simplifying complex systems. You choose the one where that which is important to you at that time is preserved, the rest as a first approximation is fixed or ignored. Choose (or build) a different model if something else is more important to you at that point of time. Nothing sacrosanct about models. In this case choice of models become like using statistics. Would your illustrative model help if you were working out the algorithms which determine how much of fuel to deliver?

In larger engines the governor module is separate, even if electronic. In smaller modern engines the 'governor' is a separate routine in the ECU. Does not take away from the fact that governors irrespective of type, intimately and directly determine the quantity of fuel an engine gets. Look at its function. I'm convinced the governor should be considered part of the fueling system.


Cruise control is an input to the governor. As is the driver. Both decide how fast you want to go. They determine 'target speed'. Some other module/ mechanism then determine fueling needs and takes action. To illustrate a different viewpoint, just use a different model.

Regards
Sutripta
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Old 11th July 2017, 00:06   #33
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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
Lets agree to differ.
Agreed, it has happened before, it might happen again!


Quote:
Originally Posted by Sutripta View Post
Models are used for simplifying complex systems. You choose the one where that which is important to you at that time is preserved, the rest as a first approximation is fixed or ignored. Choose (or build) a different model if something else is more important to you at that point of time. Nothing sacrosanct about models. In this case choice of models become like using statistics. Would your illustrative model help if you were working out the algorithms which determine how much of fuel to deliver?
If itís only a simplified representation of a system I doubt you would be able to work out any algorithm.

But yet, in this model it would certainly show various parts, be it mechanical, sensors, actuators, electrical, electronically or otherwise that would be involved and need to be taken into consideration. But you most likely need to drill into details of the various various components.


Quote:
Originally Posted by Sutripta View Post
In larger engines the governor module is separate, even if electronic. In smaller modern engines the 'governor' is a separate routine in the ECU. Does not take away from the fact that governors irrespective of type, intimately and directly determine the quantity of fuel an engine gets. Look at its function. I'm convinced the governor should be considered part of the fueling system.
As agreed, we have a different view.

With hindsight, maybe we should have discussed/agreed upon what the purpose of the ďfueling systemĒ as we were discussing really is. Are we trying to present a comprehensive overall but still simplified representation of a complex system? Or do we also want to show how this system is part of and interworking with other systems?

Letís get back on topic, because itís a very interesting experiment.

Jeroen
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Old 16th July 2017, 10:24   #34
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Default Re: Explained: Why Diesel engines need a throttle body & throttle plate

Interesting observation post TB plate delete :

I have deleted TB plate in my 1.6 S-Cross. My car is running with Wolf map and EGR is kept ON. EGR values were always fluctuating and would hit 42 percent peak before TB plate delete.

Post TB plate delete, I have observed that EGR values are not changing much. Its always below 10 percent most of the times. The peak value was 24 percent . I am planning to delete EGR fully in the map and also put a blanking delete to make it fully closed.

Stock map with EGR off = Car lost power at low end / crawling speed

Stock map with EGR On = All good

My plan is :

Wolf Map & TB plate delete : already done + EGR Off =
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