Starting Engine from a Stop

[Gros Ventre]

Gros Ventre I’m not sure I’m clear (but I am curious) on whether your digital gauge reads different. Are you saying your oil pressure (in the condition of ready / ice not running / in EV only) shows a reading different than the pics shown by Snakebitten. My dash is the same as Snakebitten. If yours is actually showing zero I wonder if they updated programming at some point. Thanks

Well, I'll have to take a picture (later today or tomorrow...) My screen layout is different than Snakebitten's, but close, so don't know what to say. At the end of the day we know the driver for the oil pressure readout is a switch not a transducer. Oil pressure at pump output varies with RPM and is limited by a spring reliever valve. I asked my dealer's techs what the idle pressure was and it's about 20psi. Notice that the pressure readout stays rock steady when engine is on regardless of rpm. The oil pump is a positive displacement pump so it's output pressure varies with rpm. The spring loaded relief valve sets the run pressure.

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[Snakebitten]

The 3.5 Ecoboost has a variable pressure oil pump. It's controlled by an electronic solenoid that you can just see the harness/connector for if you look for it.
According to Ford, if the solenoid fails, the oil pumps defaults to the high pressure position.
Interestingly Ford equipped the 7.3 liter Godzilla with an analog version of the "variable pressure" oil pump. And it too is supposed to fail to the higher pressure.

Technically the "variable" pressure is really 2-stage, in my opinion. I've monitored oil pressure on the 3.5 Ecoboost since late 2017. It's 2 stages.

And the software logic that determines which stage the solenoid puts the pump in is mostly load based, although a coldstart will keep the oil pump in high stage for a few seconds as well.

 

[Gros Ventre]

The 3.5 Ecoboost has a variable pressure oil pump. It's controlled by an electronic solenoid that you can just see the harness/connector for if you look for it.
According to Ford, if the solenoid fails, the oil pumps defaults to the high pressure position.
Interestingly Ford equipped the 7.3 liter Godzilla with an analog version of the "variable pressure" oil pump. And it too is supposed to fail to the higher pressure.

Technically the "variable" pressure is really 2-stage, in my opinion. I've monitored oil pressure on the 3.5 Ecoboost since late 2017. It's 2 stages.

And the software logic that determines which stage the solenoid puts the pump in is mostly load based, although a coldstart will keep the oil pump in high stage for a few seconds as well.

Seems odd that they would go to that complexity. In the end I suspect it is still a gerotor type pump with two stages. If so it is still a positive displacement pump with a relief valve setup of some kind. I'll have to see if I can find a picture.

 

[Snakebitten]

Seems odd that they would go to that complexity. In the end I suspect it is still a gerotor type pump with two stages. If so it is still a positive displacement pump with a relief valve setup of some kind. I'll have to see if I can find a picture.

Here yah go

 

[Gros Ventre]

Here yah go

Got it. The description is that of a single rotor gerotor type pump (positive displacement) with a solenoid operated output pressure control. I suspect that this solenoid then controls ether the spring tension or a variable orifice in the relief valve setup. The use of the default setup is a good one since loss of voltage ensures ful flow.

 

[Samson16]

Gros Ventre I’m not sure I’m clear (but I am curious) on whether your digital gauge reads different.

I can’t see any posts from @Gros Ventre for some reason. I miss western Wyoming news

 

[Snakebitten]

Got it. The description is that of a single rotor gerotor type pump (positive displacement) with a solenoid operated output pressure control. I suspect that this solenoid then controls ether the spring tension or a variable orifice in the relief valve setup. The use of the default setup is a good one since loss of voltage ensures ful flow.

The first couple of minutes of this video shows how the variable pressure pump is designed for the Godzilla version. As stated earlier, it is analog and uses a spring pressure to switch between two pumping volumes.
On the 3.5, it uses a solenoid on command from the pcm.

 

[Gros Ventre]

The first couple of minutes of this video shows how the variable pressure pump is designed for the Godzilla version. As stated earlier, it is analog and uses a spring pressure to switch between two pumping volumes.
On the 3.5, it uses a solenoid on command from the pcm.

Interesting... that's a vane type positive displacement pump with a variable volute. The solenoid then varies the spring tension to in turn vary the volute volume between hi & lo settings. Still I find it odd, given the 3,000 rpm hi/lo setting, that they'd go to this trouble. Much of this engine's hi power runs are, given the transmission ratios, done at less than 3,000 rpm. I've spent enough time on Wyoming's Interstates (I-80 & 25) that I've seen plenty of hi power output runs. Note that this is a positive displacement pump.

 

[Gros Ventre]

BTW that video explains why I cannot get the suction tube to the bottom of the oil pan. The baffle plate is what prevents that. Apparently Ford chose to reduce windage in seeking better MPG.

 

[scott011422]

BTW that video explains why I cannot get the suction tube to the bottom of the oil pan. The baffle plate is what prevents that. Apparently Ford chose to reduce windage in seeking better MPG.

I couldn’t get in that way either. I ended up modifying a drain plug and sucking it through an AN fitting right out of the drain plug.

 

[Gros Ventre]

I couldn’t get in that way either. I ended up modifying a drain plug and sucking it through an AN fitting right out of the drain plug.

I'll have to think about something like that. Right now I'm dropping the fiber undercarriage cover to get to the drain plug.

 

[Gros Ventre]

Interesting... that's a vane type positive displacement pump with a variable volute. The solenoid then varies the spring tension to in turn vary the volute volume between hi & lo settings. Still I find it odd, given the 3,000 rpm hi/lo setting, that they'd go to this trouble. Much of this engine's hi power runs are, given the transmission ratios, done at less than 3,000 rpm. I've spent enough time on Wyoming's Interstates (I-80 & 25) that I've seen plenty of hi power output runs. Note that this is a positive displacement pump.

These vane pumps have a rare failure mode. Those vanes move up & down in their slots and have a spring underneath them to push them back up as the volute expands. If this spring fails, the pump will begin losing capacity and should several fail, it could cease pumping. Not likely but for those of you that plan on keeping for the long haul, be alert.

 

[Eighthtry]

disable autostart/stop and the problem is solved.

 

[Samson16]

disable autostart/stop and the problem is solved.

The PowerBoost doesn't employ conventional auto start/stop. The truck transitions smoothly from electric to hybrid drive in most modes, and immediately when your foot lifts off the brake in sport/tow haul. I have no idea what the passenger was complaining about. To date every passenger I've had marvels at the vehicle operation.

 

[BluePB]

When not towing I am usually driving in "eco" mode. In this mode, the "lurch" sensation typically comes when pulling out into traffic from a stop and I don't have the luxury of being super smooth on the throttle. IMO when the 400hp 3.5L comes on while asking for power, feeling the transition from the 50hp electric motor is expected.

Other choices:
Sport mode = from a stop, 3.5L starts as soon as foot is off the brake pedal
Tow/haul mode = 3.5L never shuts off

If your objective is to let it rip off the line, then sport mode works really well. I'm sure that the PB is the fastest 0-60 vehicle that I have ever owned. Of course, those other modes are going to burn a small amount more fuel.

My wife has a hybrid compact SUV from another brand which I would say is much smoother on transitions from electric to gas. However, that is an entirely different drive train design that would not be practical in a truck designed to tow 12,000 pounds.

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