TPS ADC out of range

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madman4
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TPS ADC out of range

Post by madman4 »

Hi

I have a new TPS sensor.
When I get current at closed throttle I get 30
When I get current at WOT I get 1020

But in MT2.25p3 I obtain 100% of TPS before the real WOT of the throttle.

How I can fix this ?
Do I need to reduce the voltage of Vref or Vtps ?

Thx
Pat
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Matt Cramer
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Re: TPS ADC out of range

Post by Matt Cramer »

If you have the TPS getting 5 volts, the voltage is not the problem. However, your TPS may not have a full sweep to it. If that's the case, the only solution is a different TPS.

Although if you're running speed density, I wouldn't worry about it too much.
madman4
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Re: TPS ADC out of range

Post by madman4 »

Matt Cramer wrote: Although if you're running speed density, I wouldn't worry about it too much.

You're right but intellectually .... it's making an error

In fact TPS in MT reach full scale before the full scale of TBI and before the Full scale of the sensor.
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bleoh
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Re: TPS ADC out of range

Post by bleoh »

Did you calibrate the TPS?
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madman4
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Re: TPS ADC out of range

Post by madman4 »

bleoh wrote:Did you calibrate the TPS?
Yes of course

30 ADC count a closed throttle
1020 ADC count a WOT
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Matt Cramer
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Re: TPS ADC out of range

Post by Matt Cramer »

madman4 wrote:
Matt Cramer wrote: Although if you're running speed density, I wouldn't worry about it too much.

You're right but intellectually .... it's making an error

In fact TPS in MT reach full scale before the full scale of TBI and before the Full scale of the sensor.
Actually, it sounds like the sensor's full scale is smaller than the throttle's full scale! The only solution I can see is to get a different TPS with a wider range of motion.
madman4
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Re: TPS ADC out of range

Post by madman4 »

Actually, it sounds like the sensor's full scale is smaller than the throttle's full scale!
hummm for me is not the sensor full scale that is smaller than the throttle's full scale.
Because I read the full scale in megatune BUT full scale of the sensor is not reach.
If I decrease the voltage of Vref, I decrease the voltage of the TPS signal and match with the scale of ADC of the ecu ?

What is the maximum count for TPS ? 1024 ?

If 1024, decrease the Vref may be the solution, I think.
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Matt Cramer
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Re: TPS ADC out of range

Post by Matt Cramer »

1024 is the maximum ADC reading, and I'm pretty certain it corresponds to 5 volts. If your TPS is using a 5 volt VREF and putting out more than 5 volts, you have a very unusual TPS.
madman4
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Re: TPS ADC out of range

Post by madman4 »

LOL :mrgreen: :mrgreen: :mrgreen:

Unusual for sure but it is a variable resistor without electronics inside ...
I use the std 5V Vref like it was assembled in your ECU. (You sold me it in December but not I haven't finish the engine before, to test it).

I can't make any measure today I'm not at home. May be tomorrow.

The TPS datasheet is here

If I had a bad connection, TPS signal not increase and not copy the throttle position...
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madman4
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Re: TPS ADC out of range

Post by madman4 »

Finally find the problem the electric range is smaller than the physical range ....

You were right from the start then!
Again .....

Thx for your assistance.
Now need to solve the Map Daddy problem :roll:
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