53
Super Tuning!
R1100 Throttle Position Sensor Tuning - Rob Lentini
Background
Since the "R1100 Fuel Injection/Surging/Fixes" series I have continued to
investigate how the Throttle Position Sensor (TPS) works. My aim was to
develop the best procedure for a curious, competent home mechanic to adjust
this component for best performance and least "surging", the scourge of many
oilhead boxers. I went about this slowly, carefully, and enlisted the help of
others--in particular Jim Roche, AKA "Dr. Curve". Based on valuable input from
Jim and several months of experimentation on my R1100RS and other owner's
oilheads, I think what follows is a sound, repeatable, and accurate method of
adjusting the Throttle Position Sensor (TPS) for optimum performance and
driveability.
By way of review from my previous posts, recall that I found that the TPS voltage
on white-red wire #1 (from the rear) of the TPS connector should be set to .400
volts with the throttle closed. I stated that the commonly reported range of .370-
.400 was in the "ball park" but that .370, the low side, could cause reduced
throttle response and surging. I was correct in this as far as I had taken it at the
time. I know more now.
It was at this point that Jim Roche was most helpful. Jim, as many may recall,
set a flying mile top speed record with an early R1100RS. It was Jim who clued
me into the importance of monitoring and adjusting the second of the two TPS
potentiometers, white-gray wire #3 from the rear, the high speed side of the
equation. As I had previously found, wire #1 covers idle to about the 1/3 open
throttle region, and wire #3 takes over from about 1/6 throttle to WOT (wide open
throttle). Above about 3/4 open Jim reported that the oxygen sensor is ignored
and the fuel air ratio is mainly set by TPS wire #3. Jim's RS performed best with
WOT voltage at #3 under 4 volts, in his case 3.91. Above this the plugs got
sooty, and top speed performance was lost. But, at 4 volts or slightly higher
(.400 or higher at #1), throttle response at lower RPMs was improved, leading
me to conclude more TPS voltage (to an extent) was the hot setup. I've since
learned better.
Theory - "Zero = Zero"
I wondered how BMW had come up with their TPS adjustment procedure of
changing a digital reading on their analyzer from a "0" to "-0-". What this gave
was the reported voltage range of .370-.400 volts with the throttle closed. But, I
reasoned, what was the basis for closed throttle? Sure, the stop screws sealed
with blue paint set the "standard" throttle opening, but I wasn't all that convinced
(16 Seiten)
(30 Seiten)
Manymanuals.com
Manymanuals.de
Manymanuals.fr
Manymanuals.it
Manymanuals.pl
Manymanuals.cz
Manymanuals.es
Manymanuals-pt.com
Kommentare zu diesen Handbüchern