TPS questions....hypothetical situations. That fun stuff

[aheroicrevolt]

I have an 89 7MGTE manual. A year ago I rebuilt and upgraded quite a few things on it. Including getting a custom made Front Facing Intake manifold. I bought a 90MM throttle body to bolt onto it. A no brand ebay 90mm one.
A couple things I am wondering about.

1- Say the STOCK Throttle body when opening rotates clockwise, and this one to open turns counter clockwise. If I flip the TPS upside down would that compensate for that? Or would I have to flip the TB upside down and run the cable on the opposite side of the intake to make sure it rotates the same way?
2- This no name TB does not have any bypass holes on it or cut into the walls or plate itself. So when the throttle is closed, what method is the engine useing to get air into the intake? My Idle air control valve? Because my car will only stumble and cough to life if the Throttle is WIDE OPEN, but then my WIDEBAND is pegged 100% lean.

I'm wondering if my TB being upside down or the TPS being upside down, could cause my FUEL SYSTEM to believe its completely closed when its actually totally open and only dumping enough fuel for that closed. When its closed, its dumping too much fuel thinking its WO throttle and it floods out after a few cranks

is this possible?

 

[hvyman]

When looking at the inside of the tps and the tps flange on the throttle they should spin opposite each other. Also you wouldn't not be able to open throttle if one was turning the wrong way.

And no flipping it upside down would not change anything.

If you have a ffim do you have a idle air control valve hooked up?

Do you have the tps set correctly.

I'm assuming you do not have a cold start injector anymore?

All of this on the stock Ecu?

 

[aheroicrevolt]

If you have a ffim do you have a idle air control valve hooked up?
Do you have the tps set correctly.
I'm assuming you do not have a cold start injector anymore?
All of this on the stock Ecu?

YES, Still have IAC valve.
Yes, I used a multi-meter and set it up when I installed it by reading the Ohm's
Correct- deleted cold start injector
Yes- Stock ECU
My understanding is that Although it will need a tune to get the full amount of power from the extra air now, It should still idle and run pretty steady. Even drive fine not in boost?

 

[supraguy@aol]

For idle, I would assume that your TB has to be set so that a set screw will hold the throttle plate open just a hair.
Do you have a set screw on it?

 

[aheroicrevolt]

Yes it does have a set screw to adjust idle.
Should I set the screw first and Then do the TPS calibration? I did it the opposite way. I calibrated it, and then set the screw just a small amount open.

 

[jetjock]

If you're still using the ISCV the throttle plate should be fully closed. Set it first then set the TPS. When finished check that there's no code 51 with your foot off the pedal.

 

[GC89]

+1 ISCV - Idle speed control valve. Should solely control your idle so you want the tb set so it is full closed.

 

[hvyman]

And if you set tps and then moved throttle plate screw if messed with the tps calibration.

 

[aheroicrevolt]

Thanks guys, How can I test if my IACV is operating?
Then I will re-calibrate the TPS to see if it helps the starting issues.

EDIT: HOLY CRAP, I wont be getting a new IACV, $340 from Napa!!! Can I test mine to see if its working properly?

 

[jetjock]

As they say when all else fails RTFM:

http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?S=FI&P=107

You should also hear it clicking just after engine shutdown as it returns to the wide open home position. Doesn't mean it's 100% working but it's a place to begin.