Testing VF,confusing results...

[supraman74]

Thanks for the info guys and thanks for trying to help.
If my wideband is in fact reading right and my idle afr is in the 10's wouldnt that set off a rich code?
Could my TCCS be the problem?

 

[3p141592654]

The only AFR sensor in the car is the narrowband O2 sensor, and its already pegged. There is no sensor available to alert the TCSS that is its 13:1, 10:1, or 1:1!!

You need to reread JJ's discussion above of the O2 sensor.

 

[jetjock]

Well, there's code 25 and 26 but I don't want to get into them right now

 

[supraman74]

OK, so I checked wiring and all seems good, and with the safc zeroed out there is no change...
I searched for possible causes to open loop conditions but I'm not coming up with much help.
How about the tps? I unplugged it while running and no change and no codes were set.
Bad temp sensor? I need to check that to I guess.

 

[supraman74]

How about leaky injectors?

 

[3p141592654]

Since the ECU is open loop and not setting any codes, it must not be trying to run in closed-loop mode. Perhaps it is stuck in warm-up mode. This can happen if the water-temp sensor is bad, or the thermostat is stuck open and the engine never warms up.

 

[supraman74]

Thank you, as soon as I get some more garage time I'll be checking that.

 

[sneakypete]

yea, check the green ecu water temp sensor in the water neck. i broke mine once and didnt even know it.
-pete

 

[Nick M]

Thanks, I have done nothing but research. I'm no mechanic but I can do some things like read and follow directions

First good thread. Second, what you describe is what a mechanic is supposed to do. The bad ones can't do that.

 

[supraman74]

More test results...

Water temp. Sensor - http://www.supra.co.nz/87tsrm/EFI/efi116.htm
cold - 5.0
warm - .4
----------------------------------------------------------------

TPS - http://www.supra.co.nz/87tsrm/EFI/efi103.htm

Clearance----Terminals-----Resistance----Result
0mm----------vta - e2-------0.3 - 6.3-----6.2
.5mm----------idl - e2------less than 2.3---6.0
.9mm----------idl - e2------ ~ ---------6.0
full open-------vta - e2------3.5 - 10.3----- Goes to 1.0 or na?
---------------vc - e2-------4.25 - 8.25-----6.2
----------------------------------------------------------------

Voltage at ECU - http://www.supra.co.nz/87tsrm/EFI/efi38.htm
(I just listed a few)
Terminals--------Condition---------STD Voltage-----Result
idl - e2-------IG on throttle open----10 - 14----------5
vc - e2----------IG on-------------4 - 6------------ 5
vta - e2-------IG on throttle closed---0.1 - 1.0------.4
vta - e2-------IG on throttle full open---4 - 5--------3

Does my tps need adjusted or is it fubar?

 

[Buddafucco]

Is your car going rich after a warm restart?

 

[supraman74]

Yes, it goes rich after a warm start.

 

[Buddafucco]

I've been dealing with this as well. I've been lazy about it rescently.
I'm thinking that when you start the car, it goes into an open loop warm up mode (like somebody already said) and doesn't come out of that mode untill a warm restart happens. One of the sensor signals is supposed to trigger it out of warm up mode but its not happening.
I've tested about everything I can think of by the book. I'm thinking that the signal to cancel warm up mode isn't something the tsrm tells us how to test for. Something like a frequency test for the tps, etc...
I accidentally smashed my coolant temp sens. I replaced it & the connector. No change in the rich start. Just for shits & giggles I tryed a different ecm I had lying around. No change.
This is my latest theory. I don't want to lead you off track so take my "theory" with a grain of salt.

 

[supraman74]

I'm willing to listen to any theory at this point. :1zhelp:
I read somewhere that the car should enter closed loop about a minute or so after start-up, I'm not sure if thats correct though...
What I've been trying to do is figure out what would cause the ecu not to enter closed loop.
Maybe my car is entering closed loop when it should, maybe its not, I dont know.
I do know as soon as the throttle is pressed I go into open loop, like the ecu thinks I'm going woot when I'm not.
The tps tests were out of range so I'm trying to read up more on that...

 

[supraman74]

Anyone know if powering both my maft and safc using +B1 (efi main relay) would cause problems?

 

[Dirgle]

Anyone know if powering both my maft and safc using +B1 (efi main relay) would cause problems?

http://www.supramania.com/forums/showthread.php?t=61355&highlight=maft-pro

Look at post #6


Also, straighten out your TPS problem first, It is a very important sensor, and the ecu relies heavily on it. Issues with it can create a wide arrangement of odd issues. Verify it is 100% good, and you will save yourself a lot of headaches.

 

[supraman74]

Thanks for the link, good read...
I'm not sure if those tps readings I got mean that it needs adjusted or if it just kaput.
How do I verify that its 100% good?

 

[Dirgle]

Well just glancing at what you have in your list up there, mainly what IDL is doing, I think it is out of adjustment.

Refer to this page:
http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?S=FI&P=103

It's the same as the 87 one.

If you still suspect that the sensor might be bad, a couple of checks are:

**These are just basic checks to see if the sensor is functioning, even if it passes these it might be so far internally out of calibration that it is bad.**

place an ohm meter on:


IDL & E2: As you move the throttle toward full open, the meter should show an open at some point. If it doesn't the sensor is bad.

VTA & E2: It should show a smooth rise and fall of resistance values as you vary slowly sweep the throttle from full open to full closed, if you see rapid fluctuations in the values as you preform this sweep, or it exceeds the value of VC & E2 by more than 2.05 K ohms at full open, then it is bad.

VC & E2: It shouldn't show an open, this value is also needed for the previous step.



My guess is it's just out of adjustment, the TPS isn't showing that the throttle plate is coming out is IDL properly.

 

[supraman74]

OK, when I do the sensor check vta to e2 with the throttle closed
I get 6.2 but sometimes its touchy, or bounces to 1. on the digital gauge like its not getting a reading and then come back to the 6.2.

And again with vta to e2 and throttle in any position other than closed I get 1. like its not reading, its doesnt slowly change either its just instant.

 

[Dirgle]

Hmm, I'm going to say you have a flaky TPS, do you have access to a known good, working TPS?