TPS 9%/1.xx v @ idle, is this normal?

[ChiGGz]

I was playing around learning DSMLink today and noticed TPS while the car was in neutral. Shouldn't this be reading 0?

 

[effektz]

around 0% you should have. But 9% is kind of high IMO. You might want to check the sensor. When was the last time you replaced it? Also check the throttle cable and see if it may be too tight. Got to start small and elimate the easy problems

 

[ddavisaf]

10% TPS reading at idle is actually normal. You can have your throttle plate completely closed or you would not be getting air to the engine. At 0%, your car is shut off due to no air. Air and fuel mix with spark to produce combustion.
Your O2 sensor however should not be at 1.xx V's. This would mean that your A/F mixture is way off. At idle your O2 voltage should be cycling from lean to rich. Soo... here's what I recommend. Try replacing the O2 sensor. Even if it's just someone else's you know just to see if your readings change. If they don't, I would inspect the capacitors on your ECU following this guide.
http://www.tmo.com/howto/ecu1g/caps.htm

 

[ChiGGz]

I don't know about O2 Voltage, I was actually talking about the TPS voltage, is there a correlation between the two?

 

[ddavisaf]

Doh!

I'm unsure of the voltage at the moment. However I do know that 10% TPS reading at idle is perfectly normal.
S-AFC2 saying the TPS is at 0% when they're actually at 10% because it's easier for that unit to understand what's going on. DSMLink is a real tuning device that will show you exactly how your car is performing.

 

[Opiatool]

TPS Voltage should be 5 volts at 100% or pretty close to it. 1 volt is possible at idle.

I know a friend of mine's Miata gained another 6hp at the wheels by us modifying the TPS sensor so it read 4.92 volts at 100% rather than the 4.67 volts it was reading stock.


Edit: There is no DIRECT connection between TPS and O2 voltage other than supplying more throttle (thus increasing TPS voltage) would change the amount of O2 the sensor is reading and thus O2 voltage MIGHT change.