I was playing around with my scanmaster today (still trying to learn all the different functions) and I noticed that my TPS voltage was at .92V. I thought that the max that you would want was .90V? Anyway, besides that I can only get 90% (Throttle Position Percantage, TPP) when attempting to go WOT. Even once the best I could get was 84%!! Can anyone explain this to me? Is there a way to adjust these things? Thanks.

 

The only way you can adjust it, is to slot the mounting holes. For your condition, you would want to turn the TPS in the same direction the throttle blades turn. That should lower your initial reading and hopefully allow you to get more voltage at WOT to reach 100% throttle. .65v initial, seems to be a good reading to shoot for.

You know that all you need is the key ON to watch the readings, right? The engine does not have to be started.

 

Thanks Shoebox, you're always there to help someone out . Now how do you slot the TPS? Isn't it the little black "box" on the passenger side of the TB? All I see is two hex like bolts that screw it in. Is there something I am missing? Thanks.

 

Before going to that trouble, try taking out your floor mat and trying again.

A floor mat in the way typically causes max varying TPP readings of 84% to 90%

 

I though of that, but it would not explain the .92v with the throttle closed. Unless the mat was laying on top of it, too.

 

I removed the mat just to make sure that wouldn't happen. Anyone know how to slot the TPS?

 

Yes, however, should he not get an SES light for High TPS voltage if maxing it out at 4.5 volts?



I've had my TPS set as high as .9 with throttle body blades closed for several months and no problems.

It very well could be that it is too high, but I'd try the 3 second floor mat removal mod first

I recall similar questions being asked over the years I've been hear and it is typically the floor mat getting in the way. The typical response when they go check is... "DOH!"

 

ok, shoebox, floor mat wasn't it

Twas worth a shot though

 

Remove the TPS and whittle/Dremel/file the holes to elongate them in the direction you need to go.

It's possible you might have just a little "slack" in the stock mounting holes. You could try loosening the screws and give it a gentle twist. Retighten the screws and check to see if anything has changed.

 

I agree.

 

Before you start slotting the TPS sensor, I'd check the other important parameter - IAC count. Its possible you have the throttle stop screw (can we assume its not a stock TB on a 396?) out too far and the blades can't return far enough to get the voltage lower.

I have had a problem with my TPS (Rob/Shoebox knows the background) and its no problem with the MoTeC computer that runs the engine, but I also have the stock PCM running in parallel for VSS and IAC. As long as the TPS voltage at closed throttle is less than 1.00V, the IAC circuit works fine. If it goes over 1.00V, the PCM assumes the throttle is intentionally open, and doesn't attempt to regulate the IAC motor. But I don't get any code for high TPS voltage, which seems odd.

 

Alright, figured out why I wasn't getting 100% WOT. When I installed my Vortech intake elbow I accidentally installed the hose clamp too close to the TB arm. So everytime I tried going 100% it was hitting the clamp which was at about the 90% mark. Glad that was easy.
I still can't figure out the voltage though. It''s not throwng any codes either. I'm still not sure about the slotting of the TPS. I pulled it out and then reinstalled it, and I don't see anything that I should slot. After fiddling around with everything, I'm still showing .92V.
Oh yeah, this is a 58mm BBK TB if that makes a difference.

 

So you can see 0-100% now? If so, you don't really need to worry about it. What you slot is the mounting holes on the TPS.