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Presented by Bob Pattengale
BOSCH MTS 5200 LAB SCOPE
1-800-71-TRAIN (1-800-718-7246) OR www.auto-video.com
1995 NISSAN IGNITION CASE STUDY
Pictured above is a screen capture of a CMP/CKP signal waveform taken from the IATN website.
This waveform is showing us what a known good waveform for each looks like along with the
relationship between the two.
If we take the known good wave form and compare it to the waveform taken from our subject
vehicle, you can see that the timing of the CMP sensor and the CKP sensor do not match. This
tells us that that the timing chain had been installed incorrectly.
The next day the technician disassembled the engine and did in fact find that the timing chain
was installed incorrectly by at least one tooth. After correcting the problem and reassembling the
engine, the test was run again and all of the ignition coils fired as they were supposed to and the
patterns matched perfectly verifying the repair.
