great info! I figured it was simply a calc based on TPS volts, but it didn't make sense how it could be so wrong.Originally Posted by Six_Shooter
so knowing this, how should I tune stuff dependent on TPS%? for example, I'm tuning my PE circuit now, Is it okay to tune PE by offsetting MIN TPS% for PE by 30%? So I'd set PE to 100% instead of 70% for a true 70%.
Ignore TPS % in the ADX, it's not valid.
I can't give you any solid answer on how to tune parameters that use TPS %, other than feel and trial and error. You can guestimate what the TPS percentage would be, based on volts, and the pedal under your foot.
The man who says something is impossible, is usually interrupted by the man doing it.
Alright. This is what I'll do. Thanks guys!
There should be no need to guess or do manual calculations. Try editing the adx to get what you want. In the editor you find it under the Values. Basically, the TPS Volts and TPS % should be the same on the General tab except for the upper range and alarm (5 vs 100) but the formula on the Conversion tab would change to scale it differently. I believe the raw data goes from 0-255 for 0V to 5V. Once you open the adx editor and take a look it should be fairly clear how you can edit it.
Or, try the file from this site and see if it works to give you what you want,
http://www.gearhead-efi.com/Fuel-Inj...2&d=1375131735
There's one huge flaw with that idea, TPS voltage never goes to 0, even at idle, so any conversion done on the TPS voltage is going to be incorrect. Even adding an offset does not work properly. I tried for a good long time to get an accurate TPS % on a '7747, but never got it close enough to be useful.
The man who says something is impossible, is usually interrupted by the man doing it.
I'll try this tonight! Thanks for the pointers.
Does that PCM have an internal %TPS value? If yes, how do the 0% and 100% values get set? For example, does a routine use closed throttle voltage to set 0%?
At any rate, I wouldn't call it a huge issue. That number will be closer than guessing based on your foot position....
That's the thing the internal calc stays internal and It's not fed to The ALDL datastream. Trust me guessing will be As accurate as trying to calculate based an incorrect formula from TPS voltage. Although If you go back and read what I wrote, you'll see that I suggested oobserving the TPS voltage along with knowing where your foot is.
Another part of the problem It's that you might be able get what seems like an accurate range on one vehicle probably won't be on another. The '7747 does not auto calibrate the TPS at start up like newer ECM/PCM do.
The man who says something is impossible, is usually interrupted by the man doing it.
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