730 ECM what should the TPS voltage be for each on the same car
with the 730 ECM 8D, some say .54 some say ,94 I know
the older cars are .54 can I look in the bin and see
what it should be, AUJP

 

I dont think that the TPS value is in the bin. You simply set the TPS voltage to a value that your engine likes at idle. You do this during the idle speed, IAC, TPS adjustment. This procedure is in the Tech articles. I have a '87 IROCZ. I have usually been setting my TPS at 0.60 to 0.62V at idle. On '87s, the TPS is adjustable.

 

Your tps is ajustable, the newer ones are not and I think the
value is higher, yes I know how to ajust them.

 

There are several parameters that play a role in the TPS voltage at idle. For $8D the initial TPS voltage is set to the value at location $83E5. The ECM then auto-zero's to the lowest seen TPS voltage until key-off. The base TPS setting should be equal to or less then this value.

The malfunction routines check for a max and min seen TPS voltage. The min value is the lowest voltage that the base TPS can be set to.

For AXCN the minimum value is 12 ADC counts (@ $8265)

For AXCN the maximum value is 246 ADC counts (@ $8260)

For AXCN the idle initial setting is 48 ADC counts (@ $83E5)

Converting these to a voltage the values are:

For AXCN the minimum voltage is 0.24

For AXCN the maximum voltage is 4.82

For AXCN the idle initial voltage is 0.94

So for $8D which auto-zeros the TPS it should be between 0.24 and 0.94 volts.

RBob.

 

Hi guys,

I have a strange value for WOT TPS: it shows 1.25 volts with Tunerpro
idle tps is shows 0.54.

when I look at %tps it doesn't go more than 8.5% at wot.

I got a 730 $8D

when I check voltages at the wires I have correct values (very close to 5v at wot).

This thing drives me crazy!

An ads file pb???
Help will be highly highly appreciated.

 

Yes, an issue with the .ads file is causing this. IIRC this came up recently and it was either the wrong equation or the incorrect byte from the data stream.

TPS in volts is byte 10. Equation is: Volts = N * .01961

TPS in percent is byte 24. Equation is: TPS% = N * .0.39216

RBob.

 

Hi !

Thanks for your prompt answer RBOB. I had a look at my ads file and......this is what I have!

{
dwItemType =1;
strItemComments =None;
bSeparator =0;
bVisible =1;
dwUniqueID =0;
btByteNumber =10;
btMessageNumber =1;
dwItemSizeBits =8;
dwOperation =0;
dFactor =0.019608;
dOffset =0.000000;
strItemTitle =Throttle Position;
strUnitLabel =Volts;
dwAlarmHigh =255;
bAlarmHighENable =0;
dwAlarmLow =0;
bAlarmLowEnable =0;
iRangeHigh =220;
iRangeLow =28;
iLookupTableIndex =-1;
}
{
dwItemType =1;
strItemComments =None;
bSeparator =0;
bVisible =1;
dwUniqueID =3;
btByteNumber =24;
btMessageNumber =1;
dwItemSizeBits =8;
dwOperation =0;
dFactor =0.390625;
dOffset =0.000000;
strItemTitle =TPS %;
strUnitLabel =%;
dwAlarmHigh =255;
bAlarmHighENable =0;
dwAlarmLow =0;
bAlarmLowEnable =0;
iRangeHigh =255;
iRangeLow =0;
iLookupTableIndex =-1;
}

This thing really drives me crazy!

 

Do a logging plot with KOEO and see if the voltage and % are smooth.
Could have a bad TPS.
The calculation you have currently is 100/256 instead of 255.
That isn't enough to indicate the problem you are having.

 

hi,

I did change my tps sensor with the one from my 89 convertible : same thing
then with one from an 89 corvette : same thing then I bought a brand new one : same thing !

What is KOEO ??

When I plug a volt meter with the sensor also in place and pluged to the harness, and then moving slowly the tps, the voltmeter shows increased values very smooth. (Sorry for my poor english). I mean I don't have glitch like poor "variable resistor" usually do. (french word is potentiometre, does it mean something in english too ? )

My reference 5v is correct so it's not a faulty ecm.

i'm going deeper in sillyness !

 

Ok,

I'll switch to the S_AUJP_V4 package with its bin, xdf and ads file and see what shows up!

I'll keep you posted.

by the way, a BIG thank you to all of you guys for your help and support.

I would not be able to do what I'm doing now without you.

 

Hi guys,

So I did the big jump. I switched over to S_aupj V4 1026 !

Found very interresting stuff in it. The job that has been done on this is incredible! I first want to thank guys who worked on it!

getting back to my pb:

Still get a voltage going from .54v to 1.3x
But once the car ran for about 1 minute or 2, when I play with the throtle, it shows values like 20% TPS ans even more. I was not able to monitor it cause I was looking at other stuff. But it looks like it is interpreting values correctly.

I guess there's a routine somewhere that takes lowest and highest value and do something to say ok, this is 0% and 100% right?
Is my English that bad?