be sure the floor mat is not under the pedal. That will screw you up everytime.
Check the butterfly to see if it is wide open when the pedal is on the floor.
Move the pedal slightly and have someone watch the linkage under the hood for movement as soon as the pedal moves.
loosen both screws on the tps and push the sensor forward so that the screws are resting against the ends of both slots and then rotate the top of the sensor back to set the idle tps voltage but don't allow the bottom screw to move off the rear of the slot.
I'm agreeing with dan here, I dont know who told you that 4.5 to 4.6 is just a myth. NEVER have I heard anything under that is ok. .40-.42idle and 4.6-4.62WOT. Thats it, put it there. I have heard EVERYONE say this point, I would never think 4.3 to be ok, no matter what chip I have.
Interesting reading from the old thrasher chip site:
6. What does it take to enter PE mode? Do I need to set the Throttle
Position Sensor (TPS) to read 4.8v at WOT? I've been told from what
I believe to be reliable sources that it took a MAF reading of 255
and TPS of 4.8 volts or so to enable PE mode.
That is an old wive's tale that's been propagated through the years
and has unfortunately been taken as gospel. We believe we know how
that rumour got started, but we won't go into that now! PE mode is
actually entered quite easily. A certain throttle position is
required based on RPM and a certain load must be reached, or given
enough TPS, PE will enable regardless of RPM or load. Basically,
about 20% TPS is needed to enter PE under most conditions.
The subject of max TPS reading is a sticky one, as there are folks
that are convinced that they have seen an increase in performance by
adjusting it higher. While we do not refute this, and can come up
with some possible explanations as to why, these are the facts from
the ECM software point of view:
For the 86-87 controller, there is no need to exceed 80% TPS in the
stock chip. All PE fueling multipliers are identical after 75% and
above, and for those of you racing with the AC on, the AC will shut
off after 80% TPS. There is *nothing* in the cal that does anything
beyond 80% TPS. For EFI Performance chips, there is no need to
exceed 75% TPS.
For the 84-85 controller, there may be reason to go as high as
87.5%TPS as the PE fueling leans out slightly at that level in the
stock factory chip. Again for our chips, 75% is fine.
Note that we are quoting values from the stock chip or ours. We have
yet to see any other manufacturers raise these TPS boundaries, but
it’s possible some may have, although we have no idea why anyone
would. Note also these are percentage based, and we assume a 5v
reference. If by some chance this reference was higher on a
particular car, then the TPS voltage would have to rise too. We
suspect this to be the reason some folks have successfully raised
TPS voltage to achieve gains, if these gains could definitely be
attributed to the increase in TPS alone.