Help us help you. By posting the year, make, model and engine near the beginning of your help request, followed by the symptoms (no start, high idle, misfire etc.) Along with any prevalent Diagnostic Trouble Codes, aka DTCs, other forum members will be able to help you get to a solution more quickly and easily!
98 chevy 5.7 (R) motor, long crank on first start up in morning,runs fine after. Cranksensor waveform showing 0-6 volts, compare to another vehicle and many others that all run at 0-10. Is this a concern? I swapped a used sensor. Same reading. I thought if cranksensor wasn't good these (after long cranking) would default to cam sensor? Is my voltage an issue? Thanks still new to scope usage.
Any trouble codes? If the PCM was going to a default strategy, I would figure it'd set some kind of code in the process.
The signal amplitude definitely sounds low... What do all three wires read, connected and unplugged, KOEO? Wondering about a supply problem to the sensor.
Only codes were p0171,p0174 lean but his air tube between mass air and hat was loose no clamp.I had a fuel gauge on and pressure was great in fact née pump had been installed a month ago. I checked power and grounds with it plugged in and it was 12v,with a good ground. He said usually the first crank in morning would almost go until the battery went dead,but after it started it would be fine just long period of time was the issue. I had fuel gauge on never dropped below 40 overnight and was good the second key was hit.
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