Gas vs PSD
Posting Guru
Joined: Aug 2008
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From: Sunny, Snowy, CO
2009 MY FORD OBD System for 6.4L Diesel Engine
If you read the "General Description" part, the 6.4 engine speed is determined by throttle position. However, when the wastegate closes upping boost, if no throttle position has changed, it will be the same amount of fuel with increases boost as the wastegate closes and the variable vane geometry turbo opens. That's why I see more boost climbing a hill or pulling a load, with the same throttle position. Could I hold it forever, like climbing Vail Pass without giving it more gas? Of course not. However, with small hills, it works out quite nicely and took me a bit to figure out how to drive it compared to a gasser since I was used to increasing the throttle when going up the damn things. I drove it like a gasser for a while and realized I was speeding when I got to the top of a small hill. I have nothing but hills around my house, but not so much when I get out of the mountains going to work.
If you read the "General Description" part, the 6.4 engine speed is determined by throttle position. However, when the wastegate closes upping boost, if no throttle position has changed, it will be the same amount of fuel with increases boost as the wastegate closes and the variable vane geometry turbo opens. That's why I see more boost climbing a hill or pulling a load, with the same throttle position. Could I hold it forever, like climbing Vail Pass without giving it more gas? Of course not. However, with small hills, it works out quite nicely and took me a bit to figure out how to drive it compared to a gasser since I was used to increasing the throttle when going up the damn things. I drove it like a gasser for a while and realized I was speeding when I got to the top of a small hill. I have nothing but hills around my house, but not so much when I get out of the mountains going to work.
Postmaster
Joined: Apr 2008
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From: Rogersville, TN
Bill you say that with such conviction, but yet, we have not seen an 05 outpull a 6.0...
And Josh, here is the page of your pull:
https://www.ford-trucks.com/forums/9...h-video-8.html
How come both your 5.4 and the v10 in the pulls at the beginning of that thread both start to slow down at a certain point of the hill? My PSD has never done that, no PSD I have even ridden in has done that, and no videos of any PSD on here has done that... I am anxiously awaiting morning so you can post your math to see why that is and yet the v10 and 5.4 will outpull a psd.
And Josh, here is the page of your pull:
https://www.ford-trucks.com/forums/9...h-video-8.html
How come both your 5.4 and the v10 in the pulls at the beginning of that thread both start to slow down at a certain point of the hill? My PSD has never done that, no PSD I have even ridden in has done that, and no videos of any PSD on here has done that... I am anxiously awaiting morning so you can post your math to see why that is and yet the v10 and 5.4 will outpull a psd.
https://www.ford-trucks.com/forums/9...-video-10.html
Posting Guru
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From: Sunny, Snowy, CO
You are looking at the pull where I shortshifted at about 2,000 rpm to show how mine could still accelerate because of the gearing advantage. This is the pull where I actually ran it hard. I slow down twice in this video. Once because I am going over road construction(if you listen you will hear my trailer bounce) and then I slow down to go around a turn because two cars are coming at me (one of which is in my lane) and I don't want to be tearing *** up a two lane road with traffic coming. So how about you ask why I slow down instead of assuming it's because it lacks power.
https://www.ford-trucks.com/forums/9...-video-10.html
https://www.ford-trucks.com/forums/9...-video-10.html
FTE Leadership Emeritus
Joined: Jul 2002
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From: Long Island USA
Uh, one on that first page (which probably changed by now). And does it HURT the engine? Adding diesel fuel to the oil is not something I'd like to do 
FTE Leadership Emeritus
Joined: Jul 2002
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From: Long Island USA
FTE Leadership Emeritus
Joined: Jul 2002
Posts: 42,561
Likes: 423
From: Long Island USA
If you read the "General Description" part, the 6.4 engine speed is determined by throttle position. However, when the wastegate closes upping boost, if no throttle position has changed, it will be the same amount of fuel with increases boost as the wastegate closes and the variable vane geometry turbo opens. That's why I see more boost climbing a hill or pulling a load, with the same throttle position.
Posting Guru
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From: Sunny, Snowy, CO
Going UP a hill? Neither. The wastegate closes and the vanes go to "Open"
Posting Guru
Joined: Aug 2008
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From: Sunny, Snowy, CO
IF it ever happens when I'm pulling in, I'll put it in park which kills the regen and let it do its thing when I leave next time. I put a lot of miles on mine, and it's why I bought a diesel...which I SWEAR I said when I first came to this thread. 2.7 months, and 7600 miles.
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Posting Guru
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From: Sunny, Snowy, CO
If you lose all of the studs, it will damage the engine as that exhaust manifold falls off and bounces around. Do you really belive a qt or two of diesel fuel will render an engine that hold 15qts of oil bad? You'd "grow oil" too if you didn't burn so much of it.
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From: WV
One thing about that article (I admit I didn't read it a word for word, just skimmed it), it kind of seemed like it said you won't use more fuel. That isn't true, what it ment was that the fuel ratio won't change. As you put more boost, you'll add proportional amounts of fuel, but the air to fuel ratio will not change. Not challenging anyone, just clarifying.
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From: WV
Posting Guru
Joined: Aug 2008
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From: Sunny, Snowy, CO
the RPM's drop, the PCM sees it and compensates by increasing boost. The thing is the RPM's don't drop enough for you to notice, you'll never see a 100 RPM drop. My turbo Saab works the same way, except with gas.
One thing about that article (I admit I didn't read it a word for word, just skimmed it), it kind of seemed like it said you won't use more fuel. That isn't true, what it ment was that the fuel ratio won't change. As you put more boost, you'll add proportional amounts of fuel, but the air to fuel ratio will not change. Not challenging anyone, just clarifying.
One thing about that article (I admit I didn't read it a word for word, just skimmed it), it kind of seemed like it said you won't use more fuel. That isn't true, what it ment was that the fuel ratio won't change. As you put more boost, you'll add proportional amounts of fuel, but the air to fuel ratio will not change. Not challenging anyone, just clarifying.
Lead Driver
Joined: Jul 2007
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From: Rhode Island
If you lose all of the studs, it will damage the engine as that exhaust manifold falls off and bounces around. Do you really belive a qt or two of diesel fuel will render an engine that hold 15qts of oil bad? You'd "grow oil" too if you didn't burn so much of it.
Do you know what diesel fuel does to oil and bearings? Most engine manufactures say that a maximum of 5% fuel dilution at the end of an oil change interval is acceptable. In a 15 quart oil system, that works out to about 3/4ths of a quart. You had 6.4s that were making 2-3x that.
I'd rather have my exhaust manifold come loose then restroom my internals.
Posting Guru
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From: Sunny, Snowy, CO
FTE Leadership Emeritus
Joined: Jul 2002
Posts: 42,561
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From: Long Island USA
If you lose all of the studs, it will damage the engine as that exhaust manifold falls off and bounces around. Do you really belive a qt or two of diesel fuel will render an engine that hold 15qts of oil bad? You'd "grow oil" too if you didn't burn so much of it.
But never mind that.My V10 doesn't burn oil. It never uses a drop between oil changes. None of my Ford modulars have ever used oil, using Castol GTX dino oil.
It's not irritating me whatsoever, it's just funny that a diesel owner actually says "gas pedal".
