Fuel Injection - KZN130

[asgawth]

Reference: http://www.hiluxsurf.co.uk/forums/sh...ad.php?t=62909

Folks,

I wish to understand how the fuel injection system works specifically on my KZN-130 and thus how it might be generating the intererence described.

Can anyone either describe how it works and / or describe and locate the key components or point me in the right direction?

Having poked around I can see there are four metal, probably fuel lines, running to what I am assuming is the injectors near the top of the engine on the near-side. These 'fuel lines' head down to a box (the injector/fuel pump?) on the side of the engine.

I had assumed there would be some electrics to control the injectors and it was this that was giving the problems, however, I see none

Any help mucho appreciated.

[stormforce]

the electrics will be on the fuel pump its self and not the injectors.

[surfenstein]

WHAT SORT OF INTEREFERENCE ARE YOU GETTING.if its an annoying buzz when the radio is on its propably the suppresor on the alternator.

[TonyN]

I had assumed there would be some electrics to control the injectors and it was this that was giving the problems, however, I see none

You're thinking of common rail injection systems, the Surf isn't that complicated, the pump meters how much fuel it delivers to each injector internally.

[asgawth]

To answer surfenstein:

The interference is certainly not alternator whine. Its not related to the road speed of the vehicle, but to how much the accelerator pedal is depressed and thus the amount of fuel being fed to the engine. There are some more details in the posts referenced originally.


TonyN/Stormforce:

So is that box on the side of the engine, to which the four fuel lines attach, the pump? And to repeat, so as to check my understanding, it is that box that contains the electronics that pump fuel to each injector?

If that's the case, how does it work? Is there any high current electrics? Is there any timing of the pumped fuel to the injectors? If so, is that timing circuitry in the pump too? As you can tell, I've no idea how the fuel injection bit on my Surf works

Thanks for all the help.

[stormforce]

To answer surfenstein:

The interference is certainly not alternator whine. Its not related to the road speed of the vehicle, but to how much the accelerator pedal is depressed and thus the amount of fuel being fed to the engine. There are some more details in the posts referenced originally.


TonyN/Stormforce:

So is that box on the side of the engine, to which the four fuel lines attach, the pump? And to repeat, so as to check my understanding, it is that box that contains the electronics that pump fuel to each injector?

If that's the case, how does it work? Is there any high current electrics? Is there any timing of the pumped fuel to the injectors? If so, is that timing circuitry in the pump too? As you can tell, I've no idea how the fuel injection bit on my Surf works

Thanks for all the help.

yes thats the pump which the 4 lines go to the injectors.

There are i think 4 or 5 electrical plugs on the pump which will go to the ecu the main computer thing for the truck and that with the fuel pump timing will determine the right amount of fuel to each injector.
This is how i see it works but i'm not that clued up on the electrics at all

[Apache]

I'm not familiar precisely how the Surf's injection system works, but normally the injectors are opened and closed by solenoids driven by very precise, fairly high current signals with very fast rise and fall times. The back EMF from the solenoid coils, and simply because fast rise times / square waves are very rich in harmonics and therefore broadband noise, tends to mean good possibility of radiated and conducted noise. Whether those solenoids are at the pump or at the injector itself matters not a jot.

All EFI systems suffer in this way to some extent. Obviously, mechanical injection doesn't.

[gwh200]

You are getting a fluid induced interference on your amateur radio. this a very common problem. You dont need an "electrical" reason for interference to occur. Another example of fluid interference can be found with a water pump noise, being picked up on am AM signal. the fix is generally prohibitive, costwise. you need to set up a converse signal that matches the interference. This problem occurs on a great scale with 3 phase motors, used to forward liquid, near to control systems. The electrical interference is dealt with very effectively, but fluid pulses set up interference.

[Apache]

You are getting a fluid induced interference on your amateur radio. this a very common problem. You dont need an "electrical" reason for interference to occur. Another example of fluid interference can be found with a water pump noise, being picked up on am AM signal. the fix is generally prohibitive, costwise. you need to set up a converse signal that matches the interference. This problem occurs on a great scale with 3 phase motors, used to forward liquid, near to control systems. The electrical interference is dealt with very effectively, but fluid pulses set up interference.

Gra, your tinfoil hat is too tight again mate

[BUSHWHACKER]

What the hell are you lot talking about????

Just fit a petrol engine, problem solved.

[Apache]

What the hell are you lot talking about????

Just fit a petrol engine, problem solved.

All them sparks AND an injection system?! Thats even worse!!!

[BUSHWHACKER]

All them sparks AND an injection system?! Thats even worse!!!

Easier (for me) to fault find though, I'm quite expert at it now.

[gwh200]

Gra, your tinfoil hat is too tight again mate

I had sleepless nights with water interference andy...as improbable as it sounds, it occurs really badly, especially with variable speed drive pumps. You can sheild the electrical interference, but the fluid motion will set up a minor shock. If you pump fluid in an enclosed system...say a fuel injection system...you set up an interference pattern, with a directed, over atmospheric pressure, flow and a fluids natural tendency to stay in motion...or fluid. this natural tendency in eg, water is borne out by the fact that at any time only 15% or so of the constituent molecules are cohesive. The rest of the time the molecules and their respective electrons are in motion.( i seem to remember its called brownian motion...pollen left in a jar of water will continue in motion indefinitely.)
fluid under pressure, duress or span fast enough will induce interference in anothe relectrical sytem. Its a well known phenom...phenmmo..phmeoo

thing that occurs in high pressure fluid systems in the water industry.

[Apache]

I dont doubt what you say Gra, I'm just struggling with how it could generate an EM wave - particularly one of a high enough frequency. Maybe the pressure pulses act on impellers etc causing small currents in motor coils at the frequency of the pulses?

You cant have an EM wave without electrical current flow.

[stormforce]

[quote=gwh200;635655]I had sleepless nights with water interference andy...as improbable as it sounds, it occurs really badly, especially with variable speed pumps. quote]
I would go see the doctor personally Gra or get some Tena Ladies at the ready