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When I hooked a peak scanner to my car, the tps reading was a little funny. When the car was in the ACC. position (dash lights on, but engine not running) when I pressed down on the gas pedal about 1/8 inch it was about %50 percent. Then I press down another 1/8 inch and the percentage went to 100. When the car was running it was a little better. It wasn't as drastic, but there wasn't a smooth percentage increase as the pedal went down. While driving, when I press the pedal down to increase my speed by 10mph in 4th(or any gear) there isn't a smooth acceleration. It feels like the readings that I got from the scanner. It this normal, or not?
 

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I got the same thing. What leads to the confusion is that the TPS is on the throttles, not the gas pedal. The potentiometer on the gas pedal is actually the "pedal position sensor". This however does not explain why the throttles are apparently opening 100% while the engine is not even running! Maybe someone more knowledgable can comment?

Of further interest, I just got my car back from the dealer, and had complined aboutt he same erratic fuelling and jerky acceleration. They told me this was absolutely normal; in fact they compared mine to their service manager's same year M% and said mone was better than his. I'm not one to believe everything I'm told about technical stuff, so I plan to locate the actual pedal sensor and put an ohmeter on it. Hopefully I will have a better understanding then.
 

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The TPS on the throttlebodies are Throttle Position Feedback, they should have a 5volt wire at each. I forget the voltage feedback setting of them.

At the pedal it will have
Pot #1 0.5v - 4.5v
Pot #2 0.5v - 2.0v
 
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OK more info, this time the feedback sensor(TPS).
You don't have to do this in this order you can do 2 & 3 first then 1.

1) Make sure the there is 5 volts with the igntion on to the sensor, by checking the loom connector(pin 1 and ground).
****You can turn the ign off now*****
2) Quickly you can check to see if you get 4k ohm by touching pins 1 & 3.
3) The next test would be to touch pins 1 & 2, At idle(closed throttle) this first reading should be 1k ohm. As the throttle is opened you should have a smooth reading from 1k ohm up to 4k ohm at full throttle.

Please be careful, BMW wire smoke is very expensive so DON'T let it out of the wires.:hihi:

Ah more on the pedal potentiometer.

On the top should be 4 pins, (1-2 , 3-4)
Pin 1 is a ground -
pin 2 is the paired power +
pin 3 ground -
pin 4 is the power +

On the bottom are 2 that signal the ECM and it tell the throttle motor.

:M5rev:
 

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is there a way to perform a throttle body adaptation with the carsoft program?
they are not adjusted as you drive unlike fuel injector pulses which adapt to maintain the A/F ratio. If the TPS feeback gets out of range with respect to the potentimeter the DME should go into a 'limp-home' mode.
 

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I think you might have misunderstood what I was trying to ask.

What I was trying to ask was: can "zero" the throttle body's position? On other cars this need to go though a throttle body adaptation typically though the OBDII.

Is there a way to do this with the M5?


they are not adjusted as you drive unlike fuel injector pulses which adapt to maintain the A/F ratio. If the TPS feeback gets out of range with respect to the potentimeter the DME should go into a 'limp-home' mode.
 
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