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96 No Start-Rough Run Strange? Problem
Vehicle: 1996 F250 manual trans., no eng. mods., owned since new, 125k miles.
Truck started running rough, 'cutting out', stalling then start right up. I was close to home and 'limped' back & parked it. When I tried to start again it just cranked no start at all.
I hooked up a generic OBD-II scan tool and it started but ran rough. I quickly figured out that a generic OBD-II tool is worthless for diagnosing a 1996 Powerstroke. I bought an Auto Enginuity Scan Tool with Ford software.
If you just try to start it after the glow plug light goes out, it just cranks, no start.
However, if you then plug in the OBD-II cable and start the software, it starts right up.
Something is set or reset by this action.
I've tried this six times with the same results.
Is it a badt PCM or ?
When it does start it cuts out like injectors not opening.
Using the data monitoring and tests I've found that:
KOER test: P1283 error sometimes also returns 'System Pass' when oil up to temp. sometimes.
The ICP and IPR % & V are OK at idle and increase with RPM. I tested the IPR and wiring per the troubleshooting guide and the coil, wiring to fuse and PCM continuity & voltages were also OK.
I checked the oil level at the front of the engine and it was right below the plug.
I replaced the cam position sensor. I didn't think that was it because the tach was going up to 200 RPM when cranked. It wasn't the cam sensor.
Other things noted when monitoring:
System voltage was 12.2 VDC with glow plugs on, went up to 14.4-14.6 VDC after glow plugs turned off - seems high.
"Engine Coolant Temperature Input" is pegged at 302 degrees until oil gets up to 148 degrees then it changes to 5 degrees and starts climbing. Don't know if this is a real sensor or derived. The temp. on the dash behaves normally.
Any ideas on what to replace, monitor or test to fix this?