When I have my TPS idle set at ~.57 volts the WOT voltage is only 4.1 volts. I have read that it should be >4.5 volts. Is something wrong and would this effect performance?

The butterflys are fully opened and the linkage is making a dead stop on the TB if you know what I mean.

I have also noticed that recently the car will not go to 128 blms when the car is floored. What would be causing this?

Do you think my lack of performance could be from a bad ECM?

 

Don't worry about it. This "fiddling" with the max TPS voltage that came about in the "old days" when guys were trying to engage PE sooner and used mechanical methods.

You adjust the engagement of PE via the %TPS vs RPM table within the eprom NOT by fiddling with the TPS to attain > 4.5 volts. Since you have been tuning eproms for awhile, let me answer a question with a question.

What would the TPS having a reading > 4.5 volts do for you that you don't get with 4.1 volts?

 

Obviously he did not know the answer to that or never would have asked...
I wasnt sure till now-maybe load will have used that for calculation.

 

As long as your throttle blades are completely open and the ecm is seeing 100% for the throttle position I wouldn't worry about the TPS voltage at WOT.

 

Super! Thanks all.