severe weakness that we will look at later). If an injector has a
fault where it occasionally skips a pulse, the meter registers it and
the reading changes accordingly.
Let's go back to figuring out dwell/duty readings by using
injector on-time specification. This is not generally practical, but
we will cover it for completeness. You NEED to know three things:
* Injector mS on-time specification.
* Engine RPM when specification is valid.
* How many times the injectors fire per crankshaft revolution.
The first two are self-explanatory. The last one may require
some research into whether it is a bank-fire type that injects every
360
of crankshaft rotation, a bank-fire that injects every 720 , or
an SFI that injects every 720 . Many manufacturers do not release this
data so you may have to figure it out yourself with a frequency meter.
Here are the four complete steps to convert millisecond on-
time:
1) Determine the injector pulse width and RPM it was obtained
at. Let's say the specification is for one millisecond of on-time at a
hot idle of 600 RPM.
2) Determine injector firing method for the complete 4 stroke
cycle. Let's say this is a 360
bank-fired, meaning an injector fires
each and every crankshaft revolution.
3) Determine how many times the injector will fire at the
specified engine speed (600 RPM) in a fixed time period. We will use
100 milliseconds because it is easy to use.
Six hundred crankshaft Revolutions Per Minute (RPM) divided
by 60 seconds equals 10 revolutions per second.
Multiplying 10 times .100 yields one; the crankshaft turns
one time in 100 milliseconds. With exactly one crankshaft rotation in
100 milliseconds, we know that the injector fires exactly one time.
4) Determine the ratio of injector on-time vs. off-time in
the fixed time period, then figure duty cycle and/or dwell. The
injector fires one time for a total of one millisecond in any given
100 millisecond period.
One hundred minus one equals 99. We have a 99% duty cycle. If
we wanted to know the dwell (on 6 cylinder scale), multiple 99% times
.6; this equals 59.4
dwell.
Weaknesses of Dwell/Duty Meter
The weaknesses are significant. First, there is no one-to-one
correspondence to actual mS on-time. No manufacturer releases
dwell/duty data, and it is time-consuming to convert the mS on-time
readings. Besides, there can be a large degree of error because the
conversion forces you to assume that the injector(s) are always firing\
at the same rate for the same period of time. This can be a dangerous
assumption.
Second, all level of detail is lost in the averaging process.
This is the primary weakness. You cannot see the details you need to
make a confident diagnosis.
Here is one example. Imagine a vehicle that has a faulty
injector driver that occasionally skips an injector pulse. Every
skipped pulse means that that cylinder does not fire, thus unburned O2
gets pushed into the exhaust and passes the O2 sensor. The O2 sensor
indicates lean, so the computer fattens up the mixture to compensate
for the supposed "lean" condition.
A connected dwell/duty meter would see the fattened pulse
width but would also see the skipped pulses. It would tally both and
likely come back with a reading that indicated the "pulse width" was
within specification because the rich mixture and missing pulses
offset each other.
This situation is not a far-fetched scenario. Some early GM
WIPER/WASHER SYSTEM
1998 Mitsubishi Montero
1998 ACCESSORIES & EQUIPMENT
Mitsubishi - Wiper/Washer Systems
Diamante, Eclipse, Galant, Mirage, Montero, Montero Sport,
3000GT
DESCRIPTION & OPERATION
All models are equipped with a 2-speed wiper motor with an
optional intermittent wiper feature. Some models are equipped with a
rear wiper/washer.
Galant is equipped with a wiper system that varies
intermittent setting speed with vehicle speed. System uses ignition
switch, wiper switch, intermittent switch, washer switch, vehicle
speed sensor, and Electronic Time Alarm Control System (ETACS) ECU.
COMPONENT LOCATIONS
COMPONENT LOCATIONS TABLE \
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Component Location
Assist-ECU (Diamante) ............. Above Right Kick Panel
ETACS-ECU ....................... Behind Left Side Of Dash
Wiper Relay
Front
Except Diamante &
3000GT ....................... Integral With Steering
Column Switch
Rear
Eclipse .............. Within Rear Wiper/Washer Switch
Montero &
Montero Sport ................ On Relay Block, Behind
Left Side Of Dash
3000GT ................ Behind Left Rear Quarter Panel
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ADJUSTMENTS
FRONT WIPER ARM ADJUSTMENT
Ensure wiper motor is in park position. Position wiper arm
and blade assembly so tip of blade is specified distance above front
window trim. See FRONT WIPER ADJUSTMENT SPECIFICATIONS table.
FRONT WIPER ADJUSTMENT SPECIFICATIONS TABLE
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Driver's Side Passenger's Side
Model In. (mm) In. (mm)
Diamante ....... 2.56-3.15 (65-80) .... .79-1.38 (20-35)
Eclipse .......... .19-.59 (5-15) .... 1.65-2.05 (42-52)
Galant ........... .39-.79 (10-20) ..... .39-.79 (10-20)
Mirage .......... .79-1.18 (20-30) .... .79-1.18 (20-30)
Montero ......... .98-1.38 (25-35) ... 1.38-1.77 (35-45)
Montero Sport ... .98-1.20 (25-31) ... 1.20-1.50 (31-38)
3000GT ........... .59-.79 (15-20) ..... .59-.79 (15-20)
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