TPS voltage?
Thread Starter
Le Mans Master
Joined: Apr 2001
Posts: 7,410
Likes: 252
From: Little Elm TX
TPS voltage?
Data Master shows that I'm getting 100% throttle, but my TPS voltage is only 3.75v at 100%. I thought it was "suppose" to be around 4.5v? Could this be cause any problems?
Race Director
Joined: May 2001
Posts: 14,165
Likes: 9
Re: TPS voltage? (R94 LT 1)
I found a similar thing on my car. I did a little research and have found it to be quite alright, and perfectly normal. Datamaster is actually showing 100% throttle so that means the computer is seeing it as 100% throttle. It turns out that the ECM on the LT1 will auto zero the TPS when you turn the key on. If it is anywhere between .3 and .9 volts it will see this as "0" and will go from there.
In my case zero is .31 volts, which in turn makes 100% around 3.7 like yours is. If it was higher to begin with then it would read higher at 100%, but so long as you're within that range you're cool. This is however another reason why it's very important not to put your foot on the gas when starting it. You can probably get away with it after you turn the key ON, but if you hold the pedal down a little bit and then turn the key on it will read that value as zero, and therefore when you let off completely it can do strange things because the computer would then see a negative % of throttle.
I saw the exact same thing and asked the exact same question. I found the answer in the factory service manual. :cheers:
In my case zero is .31 volts, which in turn makes 100% around 3.7 like yours is. If it was higher to begin with then it would read higher at 100%, but so long as you're within that range you're cool. This is however another reason why it's very important not to put your foot on the gas when starting it. You can probably get away with it after you turn the key ON, but if you hold the pedal down a little bit and then turn the key on it will read that value as zero, and therefore when you let off completely it can do strange things because the computer would then see a negative % of throttle.
I saw the exact same thing and asked the exact same question. I found the answer in the factory service manual. :cheers:
