01What it usually turns out to be
DME, crank sensor, or the wiring between them.
02How I actually find it
Oscilloscope on the crank signal — the waveform shows whether the sensor, the DME or the wire is lying.
03Why reading the code alone will not show it
Only a general "incorrect signal" code shows, if anything.
04What to do before bringing it in
Make an appointment and have the VIN ready.
Confirmed on cars in this shop.
This is usually diagnostics & electrical troubleshooting
Not sure yet? Send the symptom anyway — I will tell you what it involves for your car.
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