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I have '92 f250 7.3l IDI stock w/e4od trans. Early on the OCS lite would flash and the trans would shift hard. I had the codes read and the speed sensor loss was there. I replaced the sensor and the problem persisted. The OCS lite would occasionally blink and the trans would shift at high pressure. I could fix by removing power from the PCM. The trans now shifts hard always. I checked the FIPL setting per the threads and is OK. I connected a voltmeter to the EPC wires to see what's occurring. The voltage to the EPC is 3.8-4.01 when traveling or shifting. If I press accelerator down the voltage goes down which I think increases pressure. During shifts the voltage to the EPC solenoid stays fairly constant. Is the problem in the PCM or the trans?
I have '92 f250 7.3l IDI stock w/e4od trans. Early on the OCS lite would flash and the trans would shift hard. I had the codes read and the speed sensor loss was there. I replaced the sensor and the problem persisted. The OCS lite would occasionally blink and the trans would shift at high pressure. I could fix by removing power from the PCM. The trans now shifts hard always. I checked the FIPL setting per the threads and is OK. I connected a voltmeter to the EPC wires to see what's occurring. The voltage to the EPC is 3.8-4.01 when traveling or shifting. If I press accelerator down the voltage goes down which I think increases pressure. During shifts the voltage to the EPC solenoid stays fairly constant. Is the problem in the PCM or the trans?
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