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Okay, someone has to say it...

Throttle Bodies are "Technically" neither Carburetor nor true Fuel Injection. They're actually the byproduct of cross-engineering.

IMHO, I consider them to be more Carburetor than Injection, because that's essentially what they are... carbs with fuel lines in place of a Float Bowl.

Of course, if the OP had much experience with trying to keep up with a group at WOT only to have the Carburetor's bowls go dry... well then he'd understand why it's a bad idea (one of many) to try swapping out his TB system. Just my two cents, before taxes.
Please make him stop :banghead :banghead.
Some of your thoughts are best kept inside your head Josh. :lol :lol
 

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Okay, someone has to say it...

Throttle Bodies are "Technically" neither Carburetor nor true Fuel Injection.
Josh,

Normally, I love your rants, but the TL engine is absolutely fuel injected, "technically". Throttle bodies are part of the fuel injection system. Carbs use gravity (and mainly the negative pressure of the pistons) to introduce fuel, injectors use force to introduce fuel...

I don't want to get into a discussion, but yes...

The TL is fuel injected.
 

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Yeah, I knew the way in which I said this would likely bring the fire down upon me from the mountain. However I was attempting to compress, and overly simplify, information from some very looong technical documents I'd read over the years. I guess It all really boils down to context, and whether or not you consider TBI to be "True Fuel Injection".

That said, yes, TBI is technically the earliest (and least efficient) type of "Fuel Injection" system. And yes, the TL is "Fuel Injected." In fact, it says Fuel Injected (FI) right there on the cluster. At no point did I dispute either of these facts, which is why I'm not sure where the context of what I said went to poop (the fault obviously being in my writing).

IMG_0945.JPG

When you view the entire fuel delivery system configuration in it's entirety, the TBI setup more cloesly resembles that of a Carbureted system than a true Electronic Fuel Injection system, or the more modern Direct Port Injection systems. Both of which are considered by many to be "True Fuel Injection". Due to this fact, you can easily reconfigure a Carbureted system into a TBI system and vice versa, but not so with EFI or DFI.

I could go on and on (since I've already shot myself in the foot), but in the end I did the research, drank the Kool Aid, and ultimately came to agree (and I'm not alone) that the TBI is basically a modified Carburetor with fuel injected directly into it (ECU controlled) rather than pulling it (via vacuum from the engine) from tank to bowl. As such, the only real benefit I see (right or wrong) is that we no longer worry about running out of fuel at WOT.

By the way, this all stems from an argument I had with a mechanic working on my old TLR some 10 years ago. He made the comment "you need your Carburetors synced." To which I replied, "its Fuel Injected." And thus began a long argument over 'Carbureted vs true FI systems'. Naturally I conceded due to lack of knowledge. I had no answers for him when he argued over the TLR having a "Choke" like a carb, required syncing like a carb, mixed air and fuel like a carb, etc. So naturally I was like... yup, that does sound like a carb.

Okay, now I'll grab my ankles and prepare for some rigorously inserted knowledge [img= class=inlineimg]/forums/images/smilies/uhoh.gif[/img]




NOTE: Because I just so happen to be working on a TLR (TBI) and my truck (EFI) at the same time, I'm able to provide a visual of my point. Looking at this side by side comparison, tell me which one more closely resembles a pair of Carburetors <img src="http://www.tlzone.net/forums/images/smilies/confused.gif" border="0" alt="" title="Confused" class="inlineimg" />

IMG_0947.JPG
 

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But surely the bottom picture is not the whole of the fuel injection system in your truck. It looks like that is just the injector rails. There has to be some kind of inlet manifold/throttle body to control the air fuel ratio. On the TL the throttle bodies are the whole system. Throttle bodies and injectors and butterfly valves to control the air intake . Are you telling me you're comparing like for like in your 2 pictures.
Admittedly I know nothing about your trucks fuel system but it has to have a similar system you don't just have a that injector rail and nothing else. Anyway I thought efi
just stood for electronic fuel injection. Which is what I have written on the seat panel on my TLS .
As for the choke comment from your mechanic. It isn't a choke on the TL throttle bodies it's just a fast idle. It merely raises the tickover speed to aid warming up from cold without stalling.
The electronic fuel injection compensates to cold starting by enriching the fuel air ratio until the engine reaches its optimum operating temperature.

Also of course you need to sinc the trhottle bodies the same as you do carburettors it enables both cylinders to run on an equal footing. (Just trying to simplify it a bit)
You don't want one throttle bodies opening its butterfly before the other one does do you?
 

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NOTE: Because I just so happen to be working on a TLR (TBI) and my truck (EFI) at the same time, I'm able to provide a visual of my point. Looking at this side by side comparison, tell me which one more closely resembles a pair of Carburetors <img src="https://www.tlzone.net/forums/images/smilies/confused.gif" border="0" alt="" title="Confused" class="inlineimg" />

View attachment 58548
Josh,

Still missing your point...

To Gaz's point ... your fuel rail is attached to the intake manifold... aka the "throttle body"

Like I said in my previous post, not trying to argue, but you are simply wrong...

The TL is "EFI" as is your truck...

It is "electronically" fired by the ECU and "fuel injected"...
 

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Josh,

I love semantics, but I don't want some yahoo to open this thread 2 years from now and tell us "Well Josh says the TL isn't fuel injected. I own a huge boat, have some sweet ass tattoos and love drinking shitty light beer..."
 

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But surely the bottom picture is not the whole of the fuel injection system in your truck....
Sorry, didn't intentionally mean to present a biased comparison there. Truck's components a little harder to assemble.

IMG_0948.JPG

As I compare the two systems myself, they actually seem quite similar (functionally). The truck is a 2000 Frontier, so I guess it's not a huge surprise that the injection technology would be similar. Might not have been the best example to use.



On a side note, holy sh--, look at his injectors!
IMG_0949.JPG
 

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Josh,

I love semantics, but I don't want some yahoo to open this thread 2 years from now and tell us "Well Josh says the TL isn't fuel injected...
I definitely see your point. I'd go back and correct what I wrote if I could. For one, I meant to say MPI not EFI. I think I'll just quit while I'm behind, because I'm either unable to explain myself clearly, or like you said, maybe I'm just wrong (probably the latter).

So for any future Yahoos who read this... the TL is Fuel Injected.
 

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In defense of Josh I do see where he's coming from in his reasoning. All it is is a slight misconception about what defines "fuel injection". It's less a function of what it looks like compared to how it operates. Sure, the TL TB setup can be viewed as visually similar to a carb setup. However despite what your truck's system looks like, in practical terms it is no different in functional terms to what the TL has. It is the difference between a measure volume of fuel being passed into the inlet manifold via injectors compared to a volume of fuel taken up as evaporate with flow meaured through a jet. Think of the injectors as being like syringes. Then compare this with fuel being drawn through a jet by atmospheric pressure. The end result is the same. It's just the mechanics of how the result is achieved that differs.
 

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Just go the whole hog and ditch the throttle body and carbs and replace with a nice big hole then fit direct injection. Bound to be the first to attempt this! :thumbup
 
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