99 & up 7.3L Power Stroke Engine and DrivetrainDiscussion of the 99 & up 7.3L Power Stroke diesel engine and drivetrain in the 1999-Up Super Duty trucks and Excursions. No gas engine discussion allowed except on transmissions and drivetrain that pertain to all models. Please confine discussion of topics in this forum to those items that are specific to the 7.3L Power Stroke engine.
Check to be sure your fuel pump is running - located on the frame rail under the driver's seat. You can also test for fuel delivery by opening the filter drain valve (yellow handle behind the filter bowl on the top front of the engine) and see if there's fuel being pumped out the drain tube above the front axle.
If you aren't getting fuel delivery, you won't get any power, and the injector spray pattern will be coarse, making the fuel that does get injected harder to ignite.
OK, the next thing I'd check is HP oil pressure. Low HP oil pressure will cause low power as well, although if it's really low, the engine won't even start. If you don't have a scan tool that will read ICP, then you can try pulling the ICP sensor connector off and start it up.
Also check that the tin nut holding the IPR coil on is snug. If the coil can move, then the HP oil pressure can't be controlled like it's supposed to.
With a scan tool monitoring ICP and IPR duty cycle, at idle, you should be seeing about 450-550 psi and an IPR duty cycle of somewhere around 10 and 12%.
you either have a restriction in your intake, or it's an oil pressure problem. at the top of the pump there is an allen plug, remove the plug and get a fitting to fit in with some hose. get a jug or can and start the engine. oil is going to come out of that hose but engine will still run. if you have a nice steady flow and no bubbles it's ok. if you have bubbels and a choppy flow, it's an oil pressure problem or a pick up tube issue. hope this helps
18 or 19% is a little high for the IPR duty cycle at idle. You should be down around 11% at idle. The higher numbers would lean to an issue, but it doesn't indicate where. The PCM is looking for a target RPM at idle, and increases the IPR duty% to achieve it. Leaking o-rings on the IPR could lead to the higher numbers, a sticky IPR needle, leaking injector o-rings, bad oil, the list can go on. You're going to have to do a few tests to start narrowing it down from system to components. The white smoke is unburnt diesel. That's easy enough. Why is a bit harder. If there is insufficient fuel in a cylinder, it won't explode because the A/F ratio is wrong. It will start to burn but the violent air currents will snuff it out and push it out the exhaust. A bad injector tip might put the correct amount of fuel in, but not atomize it, and again- no explosion.
First, ensure your oil is correct for the truck and within mileage. Make sure the air filter is clean, and you already looked at the fuel filter. Next, get the On-Demand-Tests performed, KOER, CCT, and injector buzz. These will help narrow it down to a particular system or cylinder as the problem.
__________________ Tom
99.5 PS CC 4x4 SRW ZF-6
Triple Pillar Gauges; Fuel pres, Pyro, Boost
AE, Alldatadiy, and half a clue
- AKA "The Big White Truck"
That should put the injectors low on the list of possibilities, but the o-rings can still get damaged during the install. You should still try to get a CCT to see if it's a problem cylinder or if its a system wide issue.
__________________ Tom
99.5 PS CC 4x4 SRW ZF-6
Triple Pillar Gauges; Fuel pres, Pyro, Boost
AE, Alldatadiy, and half a clue
- AKA "The Big White Truck"
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