morgsie

iTrader: (1)

After a year I finally got my TBI project finished and running. I have a question about what the closed throttle TPS voltage should be. I am have a 454 TBI and an adjustable TPS that I bought from dctrumpet. Controlling with rbob's EBL. I installed the TPS flush with the bottom of the TB. When doing one of my first KOEO test I pushed the throttle down to WOT and it only went to 85%. Having setup my TV cable I already confirmed the gas pedal does indeed open the butterflies fully. So, I loosened the TPS and adjusted it as far as I could clockwise. After rechecking it now goes all the way up to 100% on the WUD. My question is in diagnose it shows the closed throttle (0%) @ 1.1V. I thought it should be ~.53V?

Should I be concerned as the TPS appears to be operating correctly? Do I have the wrong TPS sensor?

1991sleeper

iTrader: (-3)

I believe the tps closed voltage is between .5-.7v is considered ok ...
At what point does it hit 100%? Just as ur foot is on floor ? Or a lol bit before ? I really don't think it's gonna hurt anything either way

morgsie

iTrader: (1)

My go pedal is doing what it's suppose to as already stated. And so is the TPS at least on the WUD. However, the question still stands is it ok that my closed throttle TPS voltage is at 1.1V? I seem to remember the reading the '746 resets the TPS once they key is turned on...

RBob

iTrader: (1)

No good, TPS voltage needs to be between .4 and .8 volts. Set the TPS to a lower voltage then adjust the TPS gain parameter in the calibration. First one after the SA - parameters:

TPS - ADC Gain Term for TPS%

RBob.

morgsie

iTrader: (1)

Is there a preferred voltage to shoot for? My shop manual states idle voltage should be .31 to .41 at idle with throttle closed, but this is for the old style TPS (flat connector) where I am using the new style (round connector).

RFmaster

Shoot for 0.60 to 0.65 Volts at idle. Check minimum idle screw and throttle linkage (throttle cable) preventing throttle shaft from settling into its actual idle position. Happened to me on one occasion.

//RF

morgsie

iTrader: (1)

I set the TPS sensor even with the TB, this worked out to .6V. I then adjusted the "TPS - ADC Gain Term for TPS%" a little bit at a time until I got it to go to 100%. I think it started out with a value of 96 and ended up with a value of 109.

My next question, if I feather the throttle I can see the TPS voltage go from .6 to .7, but the WUD won't show 1% until I am around .8V. Is this normal operation?

RBob

iTrader: (1)

At key-on, engine-off, that is normal. The ECM doesn't learn the lowest seen TPS setting until the engine is running.

And even if the engine is running, the math works out:

((.8 - .6 ) * 109 * 4 ) / 256 = 0.34%

So right around .88 v it will show 1% TPS (take into account rounding).

RBob.

morgsie

iTrader: (1)

So is it ok that I set my TPS gain with KOEO?

RBob

iTrader: (1)

That is the way I do it. It just means that the ECM will see & report 100% TPS shortly before it actually occurs. It isn't something I worry about.

RBob.