ECM Swaps?? (1 Viewer)

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TheBlackSheep

TheBlackSheep

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Apologies in advance if this has already been addressed! I couldn't find anything on a quickish search of the forums.

My 88 FJ62 (with a 5 speed manual swap) has an electrical gremlin upon start up where it doesn't seem to be getting enough fuel, perhaps? If you start, then give her a rev and/or pull out the throttle control, she'll keep running, but if ya don't, she will sputter, chug, flounder, and die. I've been throwing parts at it for a year or more with zero improvement (novice, learning as I go and trying to pay attention to people who seem to know more than I do). The resident Toyota guy in my neck of the woods suggested that it was because I had an ECM for an automatic, but the H55 manual transmission.

Any of you who did the manual swap on your traditionally automatic rigs have any issues? Did you swap the ECM for one out of a stock manual? Does it even matter?

Thanks in advance!
 
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As far as I know, the ECU on the 62 doesn't talk to the automatic transmission. There also weren't any EFI Landcruisers with manual transmissions sold in the USA - so no ECU.
I have no idea why your engine isn't happy, but it's not because it's now bolted to a manual gearbox
 
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The 3FE ECU has no idea what transmission is behind it.

how do you know that it’s not getting enough fuel? Or are you just guessing?
 
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I swapped in a 5 speed and use the neutral safety switch to function as a kill switch. Once started, if I return the kill switch to where it disengages the neutral safety my engine idles up (presumably since it thinks its going in gear and adjusts for the additional drag of the now non-existent torque converter). That tells me the truck knows something about what transmission is attached.

That being said I doubt it is your cause. I had stumble idle and turned out to be a crack in the intake air hose. To see if this is happening to you, get the engine started and have a friend keep the RPMs up.
While its running, squeeze your air inake hoses. If the idle drops, you have a leak.

Just happened to me two weeks ago. Photos at the end of my build thread.
 
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EscapeWagon62 said:
I swapped in a 5 speed and use the neutral safety switch to function as a kill switch. Once started, if I return the kill switch to where it disengages the neutral safety my engine idles up (presumably since it thinks its going in gear and adjusts for the additional drag of the now non-existent torque converter). That tells me the truck knows something about what transmission is attached.
Click to expand...

The EFI uses the starter signal (That your NSS is interrupting) to sequence the cold start injector. The ECU knows when you are cranking the engine to start it vs. it actually running. It sounds like your ECU thinks you are trying to start the engine when you deactivate your switch? It has no idea what the transmission is doing. The only wiring coming out of the transmission is the reverse lights and NSS (which just interrupts the starter signal wire).

I would agree on checking the main air intake hose as well. With the manual transmission the engine will definitely be able to torque itself around more, especially with older worn out motor mounts.
 
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EscapeWagon62 said:
I swapped in a 5 speed and use the neutral safety switch to function as a kill switch. Once started, if I return the kill switch to where it disengages the neutral safety my engine idles up (presumably since it thinks its going in gear and adjusts for the additional drag of the now non-existent torque converter). That tells me the truck knows something about what transmission is attached.

That being said I doubt it is your cause. I had stumble idle and turned out to be a crack in the intake air hose. To see if this is happening to you, get the engine started and have a friend keep the RPMs up.
While its running, squeeze your air inake hoses. If the idle drops, you have a leak.

Just happened to me two weeks ago. Photos at the end of my build thread.
Click to expand...
The billows are new. Sorry about the short answer my wife just handed me this. I asked her to ask the question and I thank you for the help. I will let you know what we find out.
 
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cruisermatt said:
The EFI uses the starter signal (That your NSS is interrupting) to sequence the cold start injector. The ECU knows when you are cranking the engine to start it vs. it actually running. It sounds like your ECU thinks you are trying to start the engine when you deactivate your switch? It has no idea what the transmission is doing. The only wiring coming out of the transmission is the reverse lights and NSS (which just interrupts the starter signal wire).

I would agree on checking the main air intake hose as well. With the manual transmission the engine will definitely be able to torque itself around more, especially with older worn out motor mounts.
Click to expand...
Great insight. For the life of me I couldn’t find a good reason for idle up but the cold start injector makes total sense.
 
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EscapeWagon62 said:
Great insight. For the life of me I couldn’t find a good reason for idle up but the cold start injector makes total sense.
Click to expand...

well, combination of cold start injector, IAC, ignition timing, fuel alone won’t effect RPM :)

FYI, the information I stated in my last post is inferred purely from the schematic in the back of the FSM
 
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Seth S said:
You mean like:

1. turn key
2. Engine start?

or are you talking about rudimentary ecu language?
Click to expand...
I believe the Hubs was talking rudimentary ecu language.

Ran the codes and got a 42 back, which seems to be VSS, which I don’t think the 62 has, correct me if wrong, or ecm? Does that sound right? I will try to post a video of startup tomorrow. Between landscaping and Father’s Day, I haven’t had much of a chance to dig any further.
 
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cmorley said:
Does anyone know the starting program/ procedure for the 62? Or could send me a link?
Click to expand...

the ECM in a 62 only controls 1 thing and that’s fuel injector duration. These earlier systems essentially have a chip in the box that is programmed with a data table(s). When the truck is cold the ECM looks at the throttle position, coolant temperature, and airflow sensor. Based on those three inputs it cross references the table and finds the corresponding duration value and fires the injectors accordingly. I don’t know if it does a calc on the values or straight up cross reference. I also don’t know how often the ECM samples.

the ECM may need a signal from the distributor as well for injector timing purposes.
 
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I would love to see the logic diagram or datasets that are in the ECM. I’ve seen them in more modern systems where you can monitor and tune with a laptop
 
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I'd wager one problem is you have an exhaust leak. Depending on where that leak is it could be throwing the O2 sensor readings off. Additionally you might have a vacuum leak...hose, vacuum lines, or even intake manifold gasket.

Have you done all the tune up items and steps? like cap, rotor, proper brand plugs and gap, wires, air and fuel filters, adjusted the valve clearances, and set the timing?
 
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