Why does my TPS register 85% at WOT?
08-28-2003, 09:57 AM
#1
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Car: 1989 IROC-Z
Engine: 350 Vortech Supercharged ZZ4 TPI
Transmission: T56
Axle/Gears: 3.73
Why does my TPS register 85% at WOT?
I'll tell you, this makes for some bad quarter mile times.
85% when I am standing on the pedal, pinning it to the floor, WITH NO FLOORMAT.
Why is this, and what do you have to do to fix it... is it a matter of TPS voltage or abjusting the throttle cable.
Also, my TPS reads 11% at idle (650rpm), when I am not touching the pedal at all. MY friend with a 95 T/A says his registers 0% at idle and 100% at WOT? Help me here!
85% when I am standing on the pedal, pinning it to the floor, WITH NO FLOORMAT.
Why is this, and what do you have to do to fix it... is it a matter of TPS voltage or abjusting the throttle cable.
Also, my TPS reads 11% at idle (650rpm), when I am not touching the pedal at all. MY friend with a 95 T/A says his registers 0% at idle and 100% at WOT? Help me here!
08-28-2003, 10:25 AM
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Car: 92 GTA/ 00 TA
Engine: 383/350
Transmission: 700R4/T-56
Your TPS needs adjustment. Mine was slightly off and by adjusting it gained .3 in the quarter.
Do a search on TPS adjustment. There are many good procedures on this board. Specifically look for Vader's.
Do a search on TPS adjustment. There are many good procedures on this board. Specifically look for Vader's.
08-28-2003, 01:51 PM
#3
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Car: 2003 Porsche C4S
Engine: 3.6L
Transmission: 6-speed Manual
those are percentages from 0v to 5v and are normal for scanners on MAF cars. Do the math and you'll see the values are fine.
Last edited by james_85Z28; 08-28-2003 at 11:58 PM.
08-30-2003, 01:20 AM
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Car: 89 Iroc
Engine: 383
Transmission: 700R4
Axle/Gears: 3.45
How are you determining a "percentage"?
What are your actual voltage readings at the sensor at idle and WOT?
What are your actual voltage readings at the sensor at idle and WOT?
08-30-2003, 04:36 PM
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Car: 1989 IROC-Z
Engine: 350 Vortech Supercharged ZZ4 TPI
Transmission: T56
Axle/Gears: 3.73
I used a program called ALDL 165, which I had running on my laptop and logging data while I was making a run at the track.
When I am standing on the pedal and at WOT, the highest it ever logged was 85% throttle. This is also displayed on the screen right in front of me and definetly only goes to 85% when the pedal is pinned down to the floor (with no floor mat in). Also, it reads 11% throttle when I do not have my foot on the pedal at all (idle). With the gas pedal not pressed at all, it should read 0%.
I will post a link to the Excel file of the logged data so that you can see for yourself. What is the deal with this???
Run 1 with 85% TPS at WOT
When I am standing on the pedal and at WOT, the highest it ever logged was 85% throttle. This is also displayed on the screen right in front of me and definetly only goes to 85% when the pedal is pinned down to the floor (with no floor mat in). Also, it reads 11% throttle when I do not have my foot on the pedal at all (idle). With the gas pedal not pressed at all, it should read 0%.
I will post a link to the Excel file of the logged data so that you can see for yourself. What is the deal with this???
Run 1 with 85% TPS at WOT
08-30-2003, 07:23 PM
#6
my non adjustable TPS reads about .7V with the throttle closed for some reason. at WOT it's about 4V
i thought putting in an adjustable one would solve the problem, but at WOT the voltage was even less than with the non adjustable TPS.
still dont know what the problem is
i thought putting in an adjustable one would solve the problem, but at WOT the voltage was even less than with the non adjustable TPS.
still dont know what the problem is
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09-01-2003, 08:40 AM
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Car: 1986 Pontiac TA
Engine: 383
Transmission: 700R4
Axle/Gears: 3.70
I've always set the TPS using the voltage from a meter. The factory specs call for .54 volts at idle and 4.49 volts at WOT. I have a kit that I purchased at the autoparts store. It has leads that interface the TPS with the connector and I hook the multimeter to the leads. The voltages for the TPS have a + or - of .07.
IF yours is truly off that far, you will realize a sizeable performance gain as well as a better shifting transmission.
www.geocities.com\dzperf
IF yours is truly off that far, you will realize a sizeable performance gain as well as a better shifting transmission.
www.geocities.com\dzperf
09-01-2003, 10:35 AM
#11
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Car: 2003 Porsche C4S
Engine: 3.6L
Transmission: 6-speed Manual
11% x 5v = .55v at idle - is fine
85% x 5v = 4.25v at WOT - is fine; just needs to be greater than 4.0v.
The 165 ECMs don't store %throttle info like speed density systems so scanning software bases the %throttle on a scal from 0v to 5v.
85% x 5v = 4.25v at WOT - is fine; just needs to be greater than 4.0v.
The 165 ECMs don't store %throttle info like speed density systems so scanning software bases the %throttle on a scal from 0v to 5v.
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