Nick M;970324 said:
Which is why I used the term MAY
Not sure I know what you mean by "scoped over time"
Testing VF,confusing results...
- Thread starter supraman74
- Start date
Which is why I used the term MAY
Not sure I know what you mean by "scoped over time"
I'm starting to confuse my self here. My IDL only goes to 5v as well. My Snap-on Vantage says, "open throttle more than 1.5* & voltage should jump to either 5v or 12v"?!? If the tps is unplugged and the koeo, IDL should be 12v at the harness connector right?
^ The reason for that is simple: Your Vantage doesn't know TCCS from Conventional EFI. A bit of background:
One of the primary things that distinguishes TCCS from Conventional EFI (for example Toyota's P7 system before TCCS was introduced) is that sensor voltages are based on 5 volts instead of 12. In previous posts I'd always stated IDL is pulled up to 5 volts when open. This flies in the face of what the TSRM says but since the factory TCCS manuals stipulate 5 volts I continued to go with it.
Not long ago a poster corrected me and stated it was 12 volts. Since the TRSM also states 12 volts and since I haven't checked mine in years (when I look at other cars with IDL problems I look for code 51, pull up voltage is unimportant) I bought into this claim. That was a mistake as it turns out I was correct all along. I've gone back through the documentation and it plainly states an IDL pull up of 5 volts. To be certain I went out to the car and measured it in-circuit using the factory TCCS simulator/tester: 5 volts.
That said the manuals also state certain signals on some Toyotas will be different (it depends on the pull up resistor value). Since I don't believe this applies to the MKIII you can consider the TSRM to be wrong. Wouldn't be the first time, especially if you have an early version. Just look at the stock alarm schematic in a 1987 service manual and you'll see what I mean.
I've corrected the prior posts....
One of the primary things that distinguishes TCCS from Conventional EFI (for example Toyota's P7 system before TCCS was introduced) is that sensor voltages are based on 5 volts instead of 12. In previous posts I'd always stated IDL is pulled up to 5 volts when open. This flies in the face of what the TSRM says but since the factory TCCS manuals stipulate 5 volts I continued to go with it.
Not long ago a poster corrected me and stated it was 12 volts. Since the TRSM also states 12 volts and since I haven't checked mine in years (when I look at other cars with IDL problems I look for code 51, pull up voltage is unimportant) I bought into this claim. That was a mistake as it turns out I was correct all along. I've gone back through the documentation and it plainly states an IDL pull up of 5 volts. To be certain I went out to the car and measured it in-circuit using the factory TCCS simulator/tester: 5 volts.
That said the manuals also state certain signals on some Toyotas will be different (it depends on the pull up resistor value). Since I don't believe this applies to the MKIII you can consider the TSRM to be wrong. Wouldn't be the first time, especially if you have an early version. Just look at the stock alarm schematic in a 1987 service manual and you'll see what I mean.
I've corrected the prior posts....
Well. Shit.
For a brief period of time I thought we had found a clue to the original topic puzzle.
I want to go standalone soon. I've been trying to figure out this rich restart gimick, off and on, for nearly 2 years now. It's going to erk me for the rest of my life if I don't get closure on this problem first.
Today was fiddle with the supra day. I hit it hardcore! Nothing. No problem found.
For a brief period of time I thought we had found a clue to the original topic puzzle.
I want to go standalone soon. I've been trying to figure out this rich restart gimick, off and on, for nearly 2 years now. It's going to erk me for the rest of my life if I don't get closure on this problem first.
Today was fiddle with the supra day. I hit it hardcore! Nothing. No problem found.
I believe the book was written by a translator, not the engineer. Or the engineer's english was very bad.
There are small but important technical errors here and there in all of them.
There are small but important technical errors here and there in all of them.
robbo185;970430 said:I think thats sarcasm but its hard to tell on the internet sometimes.
Not sarcasm. He said he may need an ECU, so I am pointing that most do not.
Yes to piggyback, afc-neo. Wire harness is repaired, car now throws code 22. Have no good EFI temp sensors in parts closet, picking one up tomorrow. Antifreeze in harness never made it past spill point, about 6 inches of harness length. Checked each connection in harness after repair, including shared grounds, and all is OK. I suspect I may not have noticed problem with car until antifreeze spill, and it is entirely coincidental. My car still needs a keystroke to convert between driving modes, and still shows a vf value of 0% fuel correction. My question today is, Has anyone else had EFI temp switch fails, or operate with a Code 22 for any length of time, and does it exhibit same symptoms? Thanks, Everyone.Buddafucco;968692 said:
Good stuff in here, http://www.cygnusx1.net/Supra/Library/ToyotaTech
This one has some info about open loop.
http://www.cygnusx1.net/Supra/Library/ToyotaTech/h44.pdf
and
http://www.cygnusx1.net/Supra/Library/ToyotaTech/h58.pdf
And you can take the test at the bottom of each to see if you learned anything:naughty:
This one has some info about open loop.
http://www.cygnusx1.net/Supra/Library/ToyotaTech/h44.pdf
and
http://www.cygnusx1.net/Supra/Library/ToyotaTech/h58.pdf
And you can take the test at the bottom of each to see if you learned anything:naughty:
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I wish! Life threw me a curve ball. I've been side tracked by a move and stuff. The Supra hasn't been getting the attention it deserves the past couple weeks.
I did get to check (again) the coolant & Iat temps sensors the other day. I even double checked every test in the book on them. Normal operation at this time.
I did get to check (again) the coolant & Iat temps sensors the other day. I even double checked every test in the book on them. Normal operation at this time
.An update-A different wire harness, with matching FI temp switch and time switch, cured my rich restart issue. My issue was the same as Buddafucos, and BWests. My car now operates correctly, maintaining stoich, and producing VF readings. Suspect harness, as sensors were repeatedly checked/replaced. Thanx, Mike.
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