My 2001 superduty has lost a lot of power. I have 225000 miles on it and it's a 7.3. It seems to run fine but realy slow when it cold and I have to use a lot more pettal to go the same speed I used to. Do you think the turbos bad? How can I tell?

I wouldn't jump to that conclusion nearly that fast.

Can you hear the turbo whine?
Do you have any mods done to it?
Is your Exhaust backpressure valve coming on?
Is it reaching its normal operating temperature?

Answer those, then I can try to help you more.
Dan

Next question that I forgot in there, is there a Check engine light or any Diagnostic trouble codes?
Any other symptoms?

I wouldn't jump to that conclusion nearly that fast.

Can you hear the turbo whine?

Sometimes but not as much

Do you have any mods done to it?

All stock

Is your Exhaust backpressure valve coming on?

Don't know

Is it reaching its normal operating temperature?

Yes, Heats up like it always has.

Answer those, then I can try to help you more.
Dan

when cold it will not get out of it own way, I really must be carefull when pulling out into traffic

Thanks

Is there a hissing sound that goes with this sluggishness?
does it go away when warm?

when cold it will not get out of it own way, I really must be carefull when pulling out into traffic

Thanks

Sounds about normal when the motor is cold.

Also, do you have winter blended fuel there? Winter blended fuel does not perform as well and is going to require more pedal to get the same results as it will in the summer with straight #2.

EDIT: I should also mention that before you condemn the turbo you should be looking for air leaks as well.

Sounds about normal when the motor is cold.


Mine will run just as fast when cold, If I have my Exhaust backpressure valve unplugged.

what is an exhaust back pressure valve? are you talking about a wastegate? or exhaust brake? I dont follow ford trucks at all really. The IAT on most engines have a direct corrolation to fueling. if the iat is very dirty or failed can cause low power increased MPG.

HEUI engines like the 7.3 are acutely sensitive to engine oil./.......IE Dirty oil, low oil level (even silightly low)

Heui = Hydraulic electronic unit injection. the engine uses engine oil to create injection pressure for fuel injection.

But do you have a boost guage? is it normal boost pressures? pressure test the intake and charge air cooler for leaks. is there any abnormally heavy smoke? white smoke?

what is an exhaust back pressure valve? are you talking about a wastegate? or exhaust brake? I dont follow ford trucks at all really. The IAT on most engines have a direct corrolation to fueling. if the iat is very dirty or failed can cause low power increased MPG.

HEUI engines like the 7.3 are acutely sensitive to engine oil./.......IE Dirty oil, low oil level (even silightly low)

Heui = Hydraulic electronic unit injection. the engine uses engine oil to create injection pressure for fuel injection.

But do you have a boost guage? is it normal boost pressures? pressure test the intake and charge air cooler for leaks. is there any abnormally heavy smoke? white smoke?

an exhaust backpressure valve is a feature on the 7.3L powerstrokes, used to increase backpressure, exhaust temperature, and therefore engine temperature. It's actuated by engine oil temperature, and shuts off when the engine reaches near operating temperature.

Yes, that's how the injectors work. Low oil level will make it shudder, and if it's really low, die. Dirty oil, while bad for the engine, won't reduce power.

so exactly like an engine brake sounds like. that will give hevy soot in the intake, that will coat the intake air temp sensor. that will give the ECM a false reading and change timing and fueling. a coated IAT acts as if the sensor is open. which is like the engine air intake is very cold. that retards timing and defuels.

well thats how the IAT affects Detroit series 60s and B cummins anyways.

so exactly like an engine brake sounds like. that will give hevy soot in the intake, that will coat the intake air temp sensor. that will give the ECM a false reading and change timing and fueling. a coated IAT acts as if the sensor is open. which is like the engine air intake is very cold. that retards timing and defuels.

well thats how the IAT affects Detroit series 60s and B cummins anyways.
Not exactly the same. It makes the same hissing, but not quite as loud, and it doesnt do the clatter. the clatter sound is the pressure releasing through the valves, then the valves closing.

umm... No soot in the intake, ever. when the valve closes, it reduces the amount of fuel injected.

hmm. ok that idea out the window.

Mine will run just as fast when cold, If I have my Exhaust backpressure valve unplugged.

True, but that's not what he asked about.

The OP's climate is likely mild enough that he could probably eliminate the exhaust backpressure valve without much in the way of consequences, but there is no way I would even think about doing that up here (it was -28 degrees F today and supposed to be colder tomorrow) if you want the truck to warm up.

Yes, that's how the injectors work. Low oil level will make it shudder, and if it's really low, die. Dirty oil, while bad for the engine, won't reduce power.

yes it will, and will also cause ruff idle.
when the oil gets old it areates, then foams and then the IPR has to ramp pressure to make the same power it did untill it maxes out...........


sound slike you need a set of injectors, as it runs fine once everything gets up to opt temp. they do that when they get old. start hard to if not plugged in?

run the block heater and see what you get. when it is cold out, for me, mine wil run like crap for the first few minutes. if i use the block heater i don't have that problem. everyone is right about the oil! change it religously also!

trev

fine once everything gets up to opt temp. they do that when they get old. start hard to if not plugged in?

I'd use that excuse too. :laughing: (saving for 230cc hybrids from Rosewood diesel)
You'd have to have horrible oil to get what you're talking about. I suppose it's possible.

The question for the OP is: does it hiss, and does it go away when warm? if so, its your exhaust backpressure valve. if it's over freezing or close, you can unplug this. it's a two prong plug on the intake side of your turbo, towards the bottom.

if this isn't the case, we need all the symptoms and all the answers.

I'd use that excuse too. :laughing: (saving for 230cc hybrids from Rosewood diesel)
You'd have to have horrible oil to get what you're talking about. I suppose it's possible.

The question for the OP is: does it hiss, and does it go away when warm? if so, its your exhaust backpressure valve. if it's over freezing or close, you can unplug this. it's a two prong plug on the intake side of your turbo, towards the bottom.

if this isn't the case, we need all the symptoms and all the answers.

1)11 degrees this morning started fine
2) "hiss" the only hissing the truck does, if after starting it I let it warm up for a few minutes it sounds like a jet fighter but just at itle the second you touch the gas it goes back to a normal diesel sound.
3) the last oil change was 5000 miles ago. I'll change it and the air filter this weekend. It is up to the right level
4) winter grade fuel, Yes we have winter blend

1)11 degrees this morning started fine
2) "hiss" the only hissing the truck does, if after starting it I let it warm up for a few minutes it sounds like a jet fighter but just at itle the second you touch the gas it goes back to a normal diesel sound.
3) the last oil change was 5000 miles ago. I'll change it and the air filter this weekend. It is up to the right level
4) winter grade fuel, Yes we have winter blend

Sounds like it is not the back pressure valve. A very common problem on the 7.3L is the uppipes to the turbo. Ford used some exhaust donuts and they wear out pretty quick. This can also lead to holes in the uppipes. I'm gonna need to replace mine AGAIN soon. Most people really only get about 20K out of the donuts before they become a problem.

Best solution for this is to upgrade to the IH uppipes with bellows, or something aftermarket.

uppipes (http://www.dieselinnovations.com/di.php?page=products&product=270)
uppipes (http://www.shop.blackwidowdiesel.com/product.sc?categoryId=19&productId=304)
uppipes (http://www.shop.blackwidowdiesel.com/product.sc?categoryId=19&productId=340)

Now it COULD be the turbo, especially if you have the stock intake or a K&N. The stock intake and the K&N can let thru a LOT of dust. My stock turbo when I pulled it off showed obvious evidence of damage from dust.

You can replace a turbo, but an the only full aftermarket drop in is the Garrett GTP38R which runs about $1800. Beans diesel performance has the D66 which is basically an upgraded van turbo. Its a direct replacement and is supposed to be a great performer for less than the GTP38R.

D66 (http://www.beansdieselperformance.com/store/power-stroke/-1999-2003-7-3l/turbos-upgrades/early-1999-power-stroke-bdp-dominator-66-turbo/prod_100.html)
GTP38R (http://www.dieselinnovations.com/di.php?page=products&product=4)
GTP38R (http://www.shop.blackwidowdiesel.com/product.sc?categoryId=62&productId=359)

If you really want to do it right, pony up for one of these. :smokin:

H2E (http://www.beansdieselperformance.com/store/power-stroke/-1999-2003-7-3l/turbos-upgrades/99-03-power-stroke-hypermax-h2e-turbocharger-system/prod_95.html)
Compounds (http://www.shop.blackwidowdiesel.com/category.sc?categoryId=126)

Now it COULD be the turbo, especially if you have the stock intake or a K&N. The stock intake and the K&N can let thru a LOT of dust. [/URL]


stock intakes work fine as long as they are properly serviced and latched.
Kand N's blow.


turbos that style are easy to diagnose they are bad or arent.

3 things can go bad with a turbo.
-the bearings can go bad and cause the shaft to move side to side and in and out(or lockup), and usually cause the seal to leak, or just a seal leakage only resulting in excess oil consumption.
-the wastegate system can fail. in this case a faulty acuator(leaking diampram) a broken acuator rod, or a door inside the turbo housing is cracked and bypassing exhaust gas.
- the turbo is dusted. the fins are worn form foreign objject material. bad news if your turbo is bad because its dusted, the inside of your engine looks the same way and is getting on its way to being a boat anchor......


replacing turbos because of a drievability issue on a 7.3L is a joke unless there is something wrong. if it makes full boost and doesnt have any of the above symptons it is fine.

you most likely have a fuel delievery issue.

stock intakes work fine as long as they are properly serviced and latched.
Kand N's blow.

The stock intake is a turd which doesn't flow well and barely filters at all. Even Ford knows this and came out with a replacement, which is what I have.

turbos that style are easy to diagnose they are bad or arent.

replacing turbos because of a drievability issue on a 7.3L is a joke unless there is something wrong. if it makes full boost and doesnt have any of the above symptons it is fine.

Or if you add more fuel and need more airflow to keep the extra fuel under control.

I replaced mine because it was dusted, did not flow enough, and surged bad.

you most likely have a fuel delievery issue.

There are a few other potential issues that it could be.

when cold it will not get out of it own way, I really must be carefull when pulling out into traffic

Thanks

Mine is pretty weak when its cold, with the miles you have on it some of that is just age.

How long have you had the truck?

Is the power loss new? Sudden? Gradual?

Does it run strong when its warmed up?

There are a few sensors that can go bad that will do this. I had a bad MAP sensor that made it run real weak. If the ECU thinks the boost is low it will not fuel. Also the ICP sensor could make the ECU think the HP oil is high and try to defuel as well.

Best way to check the turbo is to pull the intake. Look at it to see if there is signs of pits or dents or pieces missing. Reach in and see if there is any play in the shaft. There will be some, but not a lot.

If you are looking to keep what you have and not step up in power you can get the turbo rebuilt. ITP diesel and Beans diesel performance both rebuild turbos. Unless there is major damage there is no reason to replace it, they are rebuildable.

ITP (http://www.itpdiesel.com/store.php/products/PSD_Turbo_Rebuilding)
Beans (http://www.beansdieselperformance.com/store/power-stroke/-1999-2003-7-3l/turbos-upgrades/99-03-power-stroke-stock-rebuilt-turbo/prod_87.html)

The stock intake is a turd which doesn't flow well and barely filters at all. Even Ford knows this and came out with a replacement, which is what I have.

Or if you add more fuel and need more airflow to keep the extra fuel under control.

.

they flow fine for a stock truck and filter good if they are properly sealed.
but his truck is stock, so why would turbo flow even be in the equation?

When is the last time you changed the fuel filter. Is there any chance you have even the slightest % of bio fuel in the tank?


I would toss in a new fuel filter, you might be getting some wax looking buildup. And second I would make sure the exhause back pressure valve is staying open while driving. Ours started closing while driving in the cold for awhile. When it wasn't needed. Replaced the ebp sensor and the tube that runs from the passenger side exhaust manifold to the sensor..

they flow fine for a stock truck and filter good if they are properly sealed.
but his truck is stock, so why would turbo flow even be in the equation?

We will have to disagree the the stock intake for the 7.3 does not seal well, does not filter well and does not flow well. Again that is why Ford offers an upgrade using a filter similar to the 6l intake.

Check out www.Forddieselpower.com you will find a answer there.. Pirate is mostly off-road.. The folks at ford diesel power know Powerstroke's

I haven't read this entire thread but let my guess you have the OEM exhaust on. I have seen 7.3 with high miles make this sound when they are cold (single digets) and warming up. I think it has to do with a sooted up muffler or cat.


micky

Last weekend I change and cleaned everything I could think of. All the oil, filters, Power washed the engine. It has made a huge difference!! Seems to be running much better now. Thanks for all the help guys.