Ah yes, good point. I wasn't thinking. Thanks for the reminder on that. Trying to multitask too much at work tonight.
H151 5spd conversion in parts for sale classifieds
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Ah yes, good point. I wasn't thinking. Thanks for the reminder on that. Trying to multitask too much at work tonight.
So what are us dreamers of somewhat affordable Toyota 5 speed manuals to do? Swap an engine that requires less ECU such as a Toyota diesel?? Some kind of half cut?
If the CEL is the only issue and you vehicle doesn't misbehave because of it, just pull the cluster and remove the bulb. Fixed
Not as easy as that since the CEL testers are looking for that "modification" in cheating the test.
Ah rito, not that easy then. Well that's a bummer
Highway mileage stayed very close to the same. I MAY have gained 1 mpg highway.
However the huge gains is in city driving. Not having to spool up the damn torque converter makes for much more efficient city driving and it's very noticeable in the skinny pedal movement. When I wasn't in torque lockup it took a lot of throttle to keep constant speed. With the 5 speed I barely have to touch the pedal to keep the truck moving. Probably almost 4 mpg increase city.
I find this topic fascinating and would love to help out whoever is tackling this issue right now. With the right guys, a "fits all" solution can most likely be found.
It's sad that after putting all the money into a project like this, then someone has to worry about programming and CEL issues. As if the swap wasn't expensive enough!
It's sad that after putting all the money into a project like this, then someone has to worry about programming and CEL issues. As if the swap wasn't expensive enough!
The Toyota ECu's are notoriously "black box" like. Toyota gives no info about the internal workings and the programmings. Hugely proprietary.
@TrickyT on MUD is an EE and a computer scientist and he opened one up and pretty much found it "unfoolable" without a lot of work going into it. He gave up on it (after setting up a test jig and the whole nine-yards). The integrated engine and tranny ECU of the OBDII set up is very difficult to work with according to Tom vs the separate set up in the OBDI system.
But please feel free to begin.... Wish I had my spare ECU to donate but I don't anymore.
@TrickyT on MUD is an EE and a computer scientist and he opened one up and pretty much found it "unfoolable" without a lot of work going into it. He gave up on it (after setting up a test jig and the whole nine-yards). The integrated engine and tranny ECU of the OBDII set up is very difficult to work with according to Tom vs the separate set up in the OBDI system.
But please feel free to begin.... Wish I had my spare ECU to donate but I don't anymore.
The Toyota ECu's are notoriously "black box" like. Toyota gives no info about the internal workings and the programmings. Hugely proprietary.
@TrickyT on MUD is an EE and a computer scientist and he opened one up and pretty much found it "unfoolable" without a lot of work going into it. He gave up on it (after setting up a test jig and the whole nine-yards). The integrated engine and tranny ECU of the OBDII set up is very difficult to work with according to Tom vs the separate set up in the OBDI system.
But please feel free to begin.... Wish I had my spare ECU to donate but I don't anymore.
Well there I go not knowing what I'm talking about.
That is very interesting. I was under the impression that the ECU takes throttle position and speed signals and outputs to the transmission solenoids. Are there other sensors on the transmission itself?
Well there I go not knowing what I'm talking about.
That is very interesting. I was under the impression that the ECU takes throttle position and speed signals and outputs to the transmission solenoids. Are there other sensors on the transmission itself?
Probably in theory as simple as that. But the return feedback is what the ECU is looking for and not getting that is making the whole system go into limp mode.
Hopefully @TrickyT will hop in and clarify my statements.
2fpower
SILVER Star
Isn't it cheaper to "move" to a state that does not have the CEL standard?
For those not reading closely, the word "move" is in quotes above.
Not saying this is the thing to do.... just see folks do this from time to time to avoid things.....
Set up a LLC - $100 investment in a nice state where you have a friend.
LLC Purchases car and registers it.
Smile and drink a beer -- no while driving.
For those not reading closely, the word "move" is in quotes above.
Not saying this is the thing to do.... just see folks do this from time to time to avoid things.....
Set up a LLC - $100 investment in a nice state where you have a friend.
LLC Purchases car and registers it.
Smile and drink a beer -- no while driving.
I would presume that using the ECU from Oz would be more viable in a 93-94 here in the US. I'm not sure how that would jive with the EGR stuff we've got here (or if it would even matter).
Another win for the FJ80... I know there are a few H55 swaps behind 3FE's cruising around without this drama.
If the JDM ecu doesn't work I suppose the tranny will always bolt to a 1HD-T someday...
Another win for the FJ80... I know there are a few H55 swaps behind 3FE's cruising around without this drama.
If the JDM ecu doesn't work I suppose the tranny will always bolt to a 1HD-T someday...
On a side note if you were in an area with no CEL/emissions testing, getting the Australian OBD-less computer would also make turboing easier since you don't have to worry about the open/closed feedback loop. The guys in Australia have no problems running boost without engine management
wagonteeth
Hippoverde
So maybe I missed it, but is the issue limited to OBDII trucks and not OBDI, or is it across the board for US FZJ's? This swap is in my head, and much cheaper than a SC or Vortec or 1HDT.
wagonteeth
Hippoverde
Well, I was quoted $25K for a vortec install and a Toyota diesel is a minimum of $8K, and more likely in the $12-13 range. My 80 is a 93, so the TRD SC is not an easy option, or even possible due to no supply, so $5K looks pretty cheap in that light. I look at it as I'm not going to be shopping for a new vehicle and my 80 is paid for, so spending 5 grand on a tranny install is easy to take in. The auto, despite being the 442 and tough, is the least likable aspect of the wagon. I like driving a manual transmission.
TRD SC's will be available again soon through @cruiserdan.
They will be directly through Magnusson vs Toyota.
So that option is still available....
And IMO, the BEST option for plug and play.
They will be directly through Magnusson vs Toyota.
So that option is still available....
And IMO, the BEST option for plug and play.
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TrickyT
Hate that mud...
The Toyota ECu's are notoriously "black box" like. Toyota gives no info about the internal workings and the programmings. Hugely proprietary.
@TrickyT on MUD is an EE and a computer scientist and he opened one up and pretty much found it "unfoolable" without a lot of work going into it. He gave up on it (after setting up a test jig and the whole nine-yards). The integrated engine and tranny ECU of the OBDII set up is very difficult to work with according to Tom vs the separate set up in the OBDI system.
But please feel free to begin.... Wish I had my spare ECU to donate but I don't anymore.
There's essentially no chance at being able to completely "reverse engineer" all that goes on in the ECU. It's just too complicated a device and, as beno says, Toyota has gone out of their way to keep all information about it proprietary. I can't even find any documentation for the several integrated circuits made by Fujitsu Ten Limited that are the heart of the ECU, let alone details about the software that runs on those chips. But for the purposes of installing an H151F, it might be possible to trick ECU into thinking you still have an automatic transmission present. I say this because there's really only two key sensors associated with the AT, speed sensor #1 and speed sensor #2, and one from the engine, rpm.
Assuming you're talking about an A343F in a FZJ80, then this AT is controlled by three solenoids and these are controlled by the ECU of course. The ECU decides what gear the transmission should be in based on shifter position, vehicle speed, and engine sensors like throttle position, mass air flow (used to calculate engine load), rpm, etc and then switches on various combinations of the three solenoids accordingly. I'm sure it then expects to see speed and rpm changes as a result of switching the solenoids. You can tell this is so because there are three OBDII fault codes (P0750, P0755, and P0770) that can be thrown indicating a solenoid is stuck or closed and I'm sure those happen because the ECU "commanded" the AT to do something (e.g., shift gears or lock up the torque converter) and then did not "see" the expected change in rpm or speed. So one would need to engineer some circuitry that fooled the ECU into thinking the non-existent AT responded in the way that it should have had it still been present. This may or may not be possible. For example, the ECU may command the AT solenoids to shift into a higher gear and then expect the engine rpm to drop by some known amount based on the gear ratios of the tranny. But with the H151F you're now doing all the shifts manually and rpm changes are independent of the ECU's signals to the solenoids. This discrepancy could easily cause one of those P07xx codes to be thrown and the CEL light to come on.
To even know if it's feasible to build the required circuitry would require a significant time investment. If I was doing it, I'd tap into the various sensor and solenoid signals used by the ECU, run these through an I/O interface and record everything on my laptop computer as I drove around town and on the freeway using various driving scenarios. Then I'd look for patterns in the recorded signals and try to deduce what "commands" the ECU was sending to the AT solenoids and what sensor changes resulted from those commands. Following that I would try "what if" scenarios where I intentionally modified the sensor input the ECU received in response to its shift commands and try to determine how big a discrepancy it took to cause an OBDII fault code. Lastly I'd design and build the needed circuitry, most likely using a microprocessor and associated software, that simulated the behavior of the AT while avoiding causing any P07xx faults. Like I said, it'd be a lot of work with no guarantee of success.
Wish I could be more optimistic.
EDIT: I've read the FSM some more and basically decided there's no way to prevent the MIL light from coming on if the AT is not present. At a minimum you'll get a P0770 fault. The FSM says the ECU uses signals from the throttle position sensor, the air-flow meter, and the crankshaft position sensor to monitor the lock-up clutch for the torque converter and then compares the state of the lock-up clutch with the "lock-up schedule" stored in ECU memory to detect if there's a problem. If lock-up does not occur when it should a P0770 is thrown and the MIL comes on.
But I'm also wondering if the MIL light being on guarantees you can't pass a smog inspection. There are clearly OBD-II fault codes that have nothing to do emissions and one could make the case that an unrelated fault code, like something for the AT, should not cause you to fail a smog inspection. Heck, the MIL in my FJ comes on when it's time to change the oil and that can't be a reason to fail smog. I need to take the wife's Lexus in for a smog check soon and I'll ask the inspector about this.
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