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Hello, i have 97 7.3 powerstroke that i just put glow plugs in. (I had to remove the head because 1 was so carboned up i could not remove it. Upon startup the engine has a slight miss at idle. When you get it out on the road it is very noticable. The engine has to crank a very long time to start. Im thinking its not getting the fuel it should be. Could some of my lines not be tight or something? Any suggestions would be great. I wont see the truck again until monday. Thanks.
 

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I would try bleeding the injector lines first. While the truck is running, break each of the fuel fittings at the injector loose about a half to one turn, one at a time, until you get a nice, steady pulse of fuel spurting out. I warn you though, the fuel is under extremely high pressure, so be very careful when you do so. If you have any air in the lines, that should remove it.
 

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Its common rail heui system I dont think that will work. :D

Im not an expert at these things but I would suspect an injector wiring connection. Maybe some dirt made its way into fuel or oil side too.

You should have a service manual and access to a scan tool so you can see whats going on with systems.
 

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Hey Greg....Diesels do not have wireing on thier injectors....they have fuel lines connected to them from the injection pump. The previous post about loosening the lines to bleed the air out of the system is what you need to do. There should be a bleeder plug on the fuel filter also.
 

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I didn't remember that the 7.3L had a common fuel rail, I guess I was thinking about the older 6.5L turbo or the 7.3L nonturbo with the snake coming off the injection pump. It's possible that it is the wiring harness for the injectors, as it is built into the VC gaskets on that motor. These run about 120 a pair, so that's a rather expensive guess. It is still possible that there is an air pocket sitting in or on top of an injector, but I can't say how you would get it out. Greg is right, you do need to get a scan tool on it and find out if there are any codes that could lead you in the right direction, or to give you a specific cylinder to work with. If you can get you hands on such a tool, do an injector buzz test, that might give you some idea or which one it is. There is another test you can run, I can't remember the specific name, but it has something to do with each cylinders load contribution, which can also tell you what they are doing. Just my .02.
 

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Discussion Starter #8
Ok, well im glad i have a few people thinking like i do, that means im not a complete retard haha. I will try the fuel first thing. I will try to get a hold of a scanner so i can check stuff out a little better. Any other suggestions? My main reason for thinking it is fuel related, is how long i have to crank the engine over. THanks again
 

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The ford Powerstroke does not have an injector pump or injector lines! We rebuild these injector were I work. Sounds like a bad connection with a wiring harness in the valve cover gaskets. BE CAREFUL these wires are 115 volts dc and can give you a nasty shock. We replace all the wiring harness and gaskets just for this reason. Did you replace all of the injector orings when you had the injectors out. I hope you took the injectors out before you took the head off. If you left the injectors in the head the injector tips stick out past the head and can be damaged. If you did not replace all the orings you might have an oring leaking oil. Just for every ones info these engine have 2 oil pumps. One make 35 lbs of oil pressure while the other can make over 3500 lbs of oil pressure. It has to have 600 lbs to start. If it has a blown oring it might be hard to start because it can,t built oil pressure.
You need a good scan tool and a break out box to find the faulty cylinder.

If you need more help call me at work on Monday 1-800-280-3350 ask for Ron. I am the service manager at Acme Diesel. www.acmediesel.com
 

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The stroke doesn't need to have air bled from the lines. Right in the manual it says if you introduce air in the lines, abnormally long cranking times may be required to get it running again.

I've had air in my lines many times after replacing the fuel filter. You crank a little longer, it runs rough for 5 seconds, then smooths out fine. I doubt its air in the lines.

Diesels aren't what they used to be. Even the later 6.5L turbos are the same way. Just crank a little longer. I had one with a broken fuel gauge, so I ran it dry many times :)
 

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turbo lag......yeeeeehaaaaaaw
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I believe the power puck is a form of piggyback that increases power. An engine brake is a valve in the exhaust that builds back pressure to help slow down your truck when going downhill or have a heavy load.
 

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I can handle the engine brake.

Its simply a butterfly valve that installs in the exhaust near the engine. When you close it, it provides enough backpressure to the engine that it increases engine braking exponentially. Originally designed by the Jacobs company, that's why its often referred to as a "Jake Brake".

It works on diesels because during decelleration there is little or no fuel being injected. The engine is only pumping air. If you were to do this on a gasoline engine you would have an instantly pig-rich mixture and lots of backfiring and possibly explosions would result. Gasoline cams also have overlap when both valves are open, meaning if you 'plug' the exhaust you'll be shoving lots of still-burning hot exhaust back out through the intake valve.

The other thing is that gasoline engines don't have nearly as much compression, so the braking wouldn't be nearly as effective.

It could be engineered for a gasoline engine, but there is just no reason to go to all that work for a little braking.
 

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A power Puck is a little power adder that looks like a hocky puck that plugs into the wiring on the 24 valve Cummins engine. It will add about 70 Rear wheel HP.
The exhaust brake is a butterfly valve that closes the exhaust in a diesel and cause back pressure. A diesel has no butterfly in the throttle and has no engine vacuum. The exhaust brake simply does what a carb or injector butterfly does in the gas engine. A diesel has very little braking with out an exhaust brake.

It is just amazing the kind of HP gains you can get out of the newer diesels with just a little box or programmer. We have seen as much as 150 Rear wheel hp gains from a $350.00 programmer. We have a good customer that has done nothing but bolt ons and has 550 rear wheel HP. It is an 03 Duramax. We have seen simalar gains in other trucks also. We have only seen one engine fail with all of this it was a 99 Powerstoke, but it had way too much propane on it. It put 2 rods out the block.
 

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RPM said:
It is just amazing the kind of HP gains you can get out of the newer diesels with just a little box or programmer. We have seen as much as 150 Rear wheel hp gains from a $350.00 programmer. We have a good customer that has done nothing but bolt ons and has 550 rear wheel HP. It is an 03 Duramax. We have seen simalar gains in other trucks also. We have only seen one engine fail with all of this it was a 99 Powerstoke, but it had way too much propane on it. It put 2 rods out the block.
I work at a Ford dealer and see those "hotrodded" powerstrokes all the time. Its amazing at what they can do. I especially love the sound they make when the remove the cat and install a straight through muffler. Its sounds just like a jet engine.
 

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1969NovaSS said:
I work at a Ford dealer and see those "hotrodded" powerstrokes all the time. Its amazing at what they can do. I especially love the sound they make when the remove the cat and install a straight through muffler. Its sounds just like a jet engine.
The new 6.0 does sound like a jet with the cat and muffler removed. You can hear the turbo spool up. You are right it does sound cool.
 
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