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ok so... I really still believe in this engine!
(Would I do the 3.4 swap? Yes!)
This truck has been through hell with me! 350K miles??? Something like that?? I gave up on the speedo cable and disconnected it (also stopping the odometer) at 250k in about 2014?
I've been having fuel ratio issues.. no fuel.. ... and then it would flood. I feel like i'm chasing my tail... so I went with a somewhat major rebuild. New fuel injectors new MVAF ?MFAV ? thing... cold air intake... FULL Emissions delete... and the cheapo eBay Headers.
... and HHO -- If I can figure out how to truly control the fuel air ratio... ...
I've also been running CATless since someone stole it in 2014.
Also, I keep coming back to the idea of runnng without the computer! In order to make this all work.
I don't have air bags.. anti lock brakes... forward side or rear radar.. I don't have lane assist.. brake assist, or adaptive cruise control, let alone cruise control!! SO... ... what does the computer in These old trucks really do "FOR" you??? Or the truck??
Right! It controls Fuel Infection. And fuel air ratio... (which MY truck is failing at!! Yes I've replaced the computer. )
yet (correct me if i'm wrong... with a diagram, please) aren't all the injectors plugged in, in parallel??
Idea... do you think the MFAV/MVAF and the throttle body could be converted into a .. sort of.. kind of .. electronic carburetor?
With that in mind.. it should be possible to run without a ECU!!
Your engine ran just fine for over 300,000 miles.....
This proves that the engine works well with the EFI system Toyota designed for it. Eliminating or modifying system after system isn't going to fix your problem, and will likely introduce new problems that didn't exist before you started messing with things.
The Engine Computer in these trucks are mainly responsible for injecting the optimum amount of fuel and adjusting ignition timing based on inputs from various sensors. While these computers are basic when compared to modern vehicles, they are still more precise and have more capability to adjust to changing conditions than a carburetor.
These sensors include an air flow meter, an intake air temperature sensor, a throttle position sensor, a coolant temperature sensor, a oxygen sensor, and an engine position sensor in the distributor that tells the engine computer where the engine is in its rotation so it knows when to adjust the timing.
I agree with the above, it would be much easier to fix what ever is causing your problem(s) than it would be to re-engineer the engine management system.
WOW!! (I realize it's a bit of a crazy idea. I was hoping you'd at least consider the idea. )
But... Actually, No... the truck has not been running just fine for 300K... is been rough for several years!! It was a salvage truck when i got it back in 2012.. I didn't have much trouble with it till 2018. It's been claimed "Totaled" by more than one insurance company.. ... but i wouldn't let them take it. They wouldn't pay my claimed value.. and I needed the truck for work. But now, I haven't driven it in 2 years because of all the issues.
emissions delete was necessary.. EGR was failing and clogged.. ... and it broke on removal. ...
As for Turning the intake system into a sort of electronic carb:
Fuel injectors spray when a 12 volt power source is applied. All you need to do is Balance and Time when the injectors are sprayed, with the air being pulled into the cylinders. But if you only use the cold start injector, it would really be more about balancing the ratio than timing.
If you can sync the cold start injector. With rpms .. or .. .. Sync the cold start injector with the VAFM... MVAF(??) ... .. ..you'd be able to disconnect the cylinder injectors entirely.. the engine speed is determined naturally by the throttle body anyways.. (no throttle position sensor would be needed either)
I read a little bit about ECU piggy backing for HHO purposes... (running 2 computers) 1 computer won't think anything is wrong while the engine is running super lean.. and the idea is to let the engine do what the engine does, without trying to control it with the computer... I don't know... ...but it seems tho me if this is possible... then running without the ECU entirely should be possible too!
I guess I was hoping maybe you guys would be willing to think a little more outside the box on this.
... As for Turning the intake system into a sort of electronic carb:
Fuel injectors spray when a 12 volt power source is applied. All you need to do is Balance and Time when the injectors are sprayed, with the air being pulled into the cylinders. But if you only use the cold start injector, it would really be more about balancing the ratio than timing.
If you can sync the cold start injector. With rpms .. or .. .. Sync the cold start injector with the VAFM... MVAF(??) ... .. ...
If you're using injectors, you're driving them with electricity. If you're "balancing" anything with air being pulled into the cylinders, you're talking about ... building a computer from scratch. An enormous amount of work. There are people who do that, and they usually don't start with very old trucks, that have never run correctly, that every insurance company thinks is worth "nothing."
If you want to "get rid of injectors," you're talking about inventing the carburetor. And if you're even thinking of something like that, it suggests you've never worked with a carburetor. They really were just crude pneumatic computers, primarily using the Bernoulli effect to mix sorta the right amount of fuel into the air flow. And even though they do a terrible job at it (low fuel economy, high emissions, ...), they are an absolute PITA to fix once they get out of whack.
If you want to go head to head with Tokyo's best, and invent an automotive fuel control system that's a big improvement over what we've all used these past 30 years, I'm impressed. But you're taking on a lot.
The 1987 engineers that designed the 3vze had a set of tools and likely did the best that could be done at the time, but we have come a long way. While I agree with Scope that a carburetor would not be a great idea, folks have been customizing computers for years on Miatas and similar performance cars. A $15 microcontroller today has several times the processing capability of the original ECU, and a programmable one can account for changes (like an egr delete) or even just low compression from wear and tear. A bad situation could be optimized at least, assuming nothing is outright broken.
I've been considering Speeduino and a wideband to try and give my truck a boost, or at least get a better idea about how it is running. https://speeduino.com/home/
To my knowledge nobody has ever done an ECU swap on a 3vze, but i am starting to see cheap programmable ECUs appear that can plug into OBD1 headers, though you would likely have to run a completely custom harness with modern or at least known sensors. At $150 it makes a fun toy to play with at a minimum. Stock they support 4 injectors and 4 coils, from reading around there it seems that you could take some of the extra ignition channels and drive the last two injectors, but that is a relatively new feature and hasn't been well documented. This runs the same tuning software as Megasquirt and can even autotune similar to Fitech or other off the shelf EFI units. I think it would be a really cool project to see how simple a 3vze could be wired with 3 ignition coils and how well one could really run.
*I am not being paid for this shameless plug, but have been considering it for my 3vze for quite some time and would love to see someone do it. I live in CA and this would never get around our smog laws... even if i get it running better/cleaner than stock*
Dude put the pipe down, no one is being helpful because what you’re asking isn’t really possible, even if it was your talking about something 100% custom which is why no one has helpful information. Do you really think one cold start injector will supply enough fuel for 6 cylinders under load? Anyway... if you’re really dead set on ditching the ECM (I don’t recommend it though, you clearly have issues elsewhere that you aren’t diagnosing correctly) why not just convert it to propane?
The 1987 engineers that designed the 3vze had a set of tools and likely did the best that could be done at the time, but we have come a long way... ...
Thanks!! This and everything else you mentioned is more of what I was looking for!!
I'm definately going to return to that post!!!
Originally Posted by scope103
If you want to "get rid of injectors," you're talking about inventing the carburetor. And if you're even thinking of something like that, it suggests you've never worked with a carburetor.
Actually I have worked on carburetors before. Haven't had much trouble with carbs. My mazda B2200 had quite a simple carb simplest carb for any vehicle I've ever worked on. (A carb that got dirty very easily, but only really needed to be cleaned every few months. The slide would just stop sliding.) That carb was far simpler than The 86 honda rebel 450 I used to ride... which was the most complicated carb I've worked on! I had to modify the carburetors in various ways to keep the bike running, most people with carb issues on the 450, complain about getting the twin carbs to synchronize properly.. when really, in my opinion, the bike needed carbs that didn't use any kind diaphragm! I was close to purchasing a pair of side draft R series Keihin carbs for twin parallel upright engines typ install on the 450 (which would have still required.. ... a few slight modifications) ...but I sold the bike. Now days I have a Yamaha Road Star 1700 V-Twin carbureted, and a Suzuki Boulevard 1500 VTwin efi. (Both are Japanese versions of The Harly Road King.) The Carbs on the Yamaha have been rejetted for strait pipes and hypercharger... it's a beast and I've had no issues.. being EFI, the Boulevard is stock... .. .. for now. HAHAHA. Will it always be EFI? ? ? Who knows!! I'm thinking about some mods I'd like to do tho!!
Bringing this full circle, Of course, the Toyota 20r and 22r engines had immensely more complex carburetors than anything I've worked on, and have an electrical connector.. I've never worked on a carb with electrical connections ..
but is that one of the carbs your talking about? ... being a a difficult concept and difficult to work on?"
Thinking about the Keihin Side Draft R Series... I'm pretty sure the TRD team installed a set of these on a custom off-road V8 Tacoma.
but yes what i'm saying is, in fact, to possibly to (re)invent a carburetor.. ... ... ... ... or install some kind of newer tech to manage the 3vze fuel system... for use with HHO. For both Fuel efficiency (at lower rpms) and performance when throttled.
... ... ...
But seriously. .. Carbs don't have to be complicated!
(So this is an entire side note... but.. what the heck. He we go! I ain't got nothin better to do this week than talk about impossibilities! )
Actually... I do enjoy my travels with my loyal and trusty steed!! I might be Stubborn As.. as a Donky, and a bit of a smart one as well.. (but I'd rather be a smart one.. than a dumb ... ... ... one.) I'm a selfish guy, a little egomoniacle AND self absorbed too... and Iike my toys!! Motorcycles, sport cars, my pickup, maybe I'll fly airplanes and sail boats some day too... ... but My names not Don. I've read the book, and I know what your saying... .. ... so I hope you don't mean to insult! 😠
Or maybe your just trying to push my buttons. ... ("will he take it as an insult?")
By the way, My daily drive has Shiny new 21" Rims, with low profile tires that cost $400 each.. And i go through a full set twice a year... cuz I drive 3000 miles a week... the beer you drink.. I brought to your local distributor, before it was delivered to your store. Or maybe it was the cheese i delivered from Wisconsin to your local Walmart, Winco, Costco etc. Or the pecan pie you had. Or the California Oranges.
... you think i care what you think, when you come at me like that? ... I put food on your plate, I get paid wel doing it. But it ain't always peaches and cream. So... ... I hope you don't mean to insult.. .. ... don't be So quick to judge, based on what little you know about a person. .. .. if your not willing or able to contribute to a conversation.. it's probably better if you didn't say anything at all.
... .. .. ...
... ... ...
On another note.. Be nice to truckers, whether you or they are out the on the rode or not... they might not be the type you want to mess with... and.. ... they got a lot of time for stewing.. and you won't win an argument.
I'm not even here to argue. .. ..
but I feel like some of you people are not here.. . for what you really, claim to be here for.
the quixote reference is intended as levity; you seem to want to invest a lot of time and resources into creating a new fuel management system for a 30-yr old engine that has a decent reputation for longevity. if you are unable to troubleshoot this pretty basic fuel injection system, what leads you to believe you’ll have more success designing and creating a totally new fuel system for your truck? my belief is that you’d be better served correctly troubleshooting the system that was designed for the motor by toyota, rather than by internet forum participants.
as to your job, i hope you enjoy what you’ve chosen for a profession; i enjoy mine. we’d be better served if more long-haul lading went back to freight rails. much lower cost per ton-mile, safer, cleaner.
89 & 90 V6 Pickup and 4Runner. ... my pickup is the 88. But I doubt the injectors are wired different. The 91-95 v6 however are wired with right 3 cylinders in parallel, and left 3 cylinders in parallel, according to the Chilton's .. , and I didn't see any other wires in there when i was under the manifold, 2 wires each injector, so.. ... there is no sequentially timed spray with position of each cylinder. ... makes more sense if you realize it's not direct injection. ... but there ya go. Fuel injectors wired in parallel.
Wanna know the problem with the 3vze? People have spent decades trying to "make it better" and in reality, if you just leave it the hell alone, it'll work. Does it blow the head gaskets? Of course. Will headers solve that issue? No. What information do I have to back it? I probably have the largest 3vze exhaust thread in existence and the only thing the headers did was cost a ˟˟˟˟ load of money that could've been better spent.
I've owned 2 3vze motors and my 1st gen has been good for years and countless miles because I refuse to do anything to it besides oil changes and tune-ups. Again, if you leave it the hell alone, it'll work as intended.
my last .02? Keep it stock, put another motor in it and close the hood.
the quixote reference is intended as levity; you seem to want to invest a lot of time and resources into creating a new fuel management system for a 30-yr old engine that has a decent reputation for longevity. if you are unable to troubleshoot this pretty basic fuel injection system, what leads you to believe you’ll have more success designing and creating a totally new fuel system for your truck? my belief is that you’d be better served correctly troubleshooting the system that was designed for the motor by toyota, rather than by internet forum participants."
30 years ago really was a bad time on this planet when it came to pollution.. ... ... technology has advanced. New ideas are out there. And seriously CARBS are not as unreliable as pulle think they are.
.. do you realize the honda rebel 250 was in production with few changes for 30 years? 1 of the changes though, they went from a complex twin carb like those on my '86 450, to a simpler more superior single carb, supplying both cylinders... and they stayed with that design till 2015 or something.
And having what I've seen in the potential of HHO. It is definately worthy!
But I can't help but question the idea, that complexity of fuel systems in modern cars, might just be, to Inhibit modification..
And as much As I love my pickup for what it got me through, and how much I want it running again.. ... 12 miles to the gallon just won't do any more! If I can get 40-60mpg on my V-twin. 10 - 12 in a semi weighing in at 80,000 GCWR... (do the math.. then I should be able to get 30mpg or more in a little 1 ton pickup. ... even on 31" MTs
Even my 1700cc 800lb 100 horse power yamaha can get 35-45mpg... ... 1 rider or 2.. and Its got smaller needles, bigger jets, Strait pipes, and a hypercharger!
And then there was My Rebel 450.. which got 50mpg no matter what! A 30 year old, 500 lb bike, With 80 horses... and 50 MPG...
08-22-2020, 06:43 PM
