If I tap the Throttle Position Sensor signal line to read it from A0 on the Arduino with a 5 feet 20ga wire, will the original voltage be compromised and if so, is there a way I can add a diode or something to my tap to solve this? TY!
Yes, the signal shape will be affected by the added capacitive load. That may not make a difference to the ECU, so try it and see.
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Yes. But Arduino analog inputs have very high impedance, so the "compromise" will probably be too small to notice.
Adding other components may actually make it worse.
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Thanks y’all. Would a shorter tapped wire length (than 5 feet) reduce any effects, or would it be negligible to shorten it to 1 foot. TY
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0-5v
TY
Might be best to use short wire.
It may pick up emi.
That may distord your throttle response or it may distord your analogRead(), especially if there is no resistor at the end (causing your impedance to be 20 Mohm).
A voltage follower near the tap may prevent a lot of trouble...
On the other hand: car 'sensor' outputs often have low impedance (like wound wire tank sensors). So you might simply put a 100 ohm transistor at the end of the lead... if the sensor does not expect low impedance, this may damage the sensor...
A 5 foot wire will not affect the signal at all.
You will also need a good ground connection.
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Yep, you can for example get throttle position via OBD2 port .
I’m opening a set of air flow butterflies on a vehicle based on TPS. I’m doing it as a favor and didn’t want to spend too much time learning canbus so I didn’t consider it. I’m also looking into using a non invasive DC current sensor on a spark plug wire to get RPM instead of invasively tapping the TPS wire.
TY!
Is RPM linearly proportional to TPS
No, but it’s a better source since we want to adjust for airflow requirements and RPM is a direct relationship.
Then an inductive pickup on one of the spark plug wires would work.
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