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Connect:
•
Jumper wires between the MAF sensor and the harness connector.
•
Black test probe to the ground jumper wire.
•
Red test probe to the signal output jumper wire.
Start the engine. Note the frequency shown on the meter display at idle. Advance the throttle and note the
change in frequency.
NOTE:
Refer to the car’s service manual for correct frequency readings.
If reading is unstable, adjust the trigger level by pressing the “
±TRIG
” button repeatedly.
Dwell Measurements
Dwell is the number of degrees of distributor rotation that the points remain closed. Dwell can be measured for
1, 2, 3, 4, 5, 6, 8, 10, or 12 cylinder engines using the meter. Before measuring dwell, you need to determine
how many cylinders are in the engine.
In the Dwell mode, the meter defaults to four cylinders and negative (-) slope, so
,
4
CYL
,
, and
_
are displayed. If you want to select a different cylinder number, press the “
RANGE
” button
repeatedly to select the correct number of cylinders.
RPM IG
Breaker Pointers/
Ignition Module
Black
Red
Good
Ground
Meter setup to measure dwell:
•
Set the rotary switch to the RPM IG (
RPM IG
) setting.
•
Press the “
DWL
” button until “
”, “
4
CYL”
, “
”
, and “
_
” appears on the display.
•
Insert the black lead in the “
COM
” jack.
•
Insert the red lead in the “
” jack.