Ok, got a problem. 01 six speed . stage one jammar nozzles ,edge comp box. Holley blue.

Only code is a 1693.

The problem is when i am driving down the road in sixth gear and gradually accellerate from say 55-70mph 2 between 1800 & 1900 rpm i get a very noticable studder. If i turn the edge box off it will still do it, but not nearly as noticeable.

Fuel pressure on the filter housing is at about 13psi. it will drop when you are on it, but never drops below 5psi. Fuel volume is a half a gallon in 9 seconds. The fuel has very little air bubbles, think the size of a pin point, just enough to see.

I have taken the edge box off completly and it still does it.

I have also replaced the apps.

Also last night i dropped the fuel tank , pulled the module out and checked the lines to make sure there was no cracks, where the pump could be sucking air or anything else weird.

The injection pump is not new by any means, but has been replaced about 50k miles ago.

the last thing is that if i am sitting in neutral reving the engine with quick snaps of the pedal - 1k rpm - snap the throttle - let off the throttle at about 1500 rpm- snap it again at 1k rpm ( you get the idea ). if i do that for say 20 snaps of the throttle i will get atleast one snap where the engine bogs or hesitates.

Sorry for the long post , but if you have any suggestions, please let me know. Thanks
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Did you have your injectors pop tested when you put your nozzles on?

I've got Jammer Stage II tips in my 99 24v (installed 50k ago, 275k on the engine,) and I suspect that I've got at least 1 injector body going south. Occasionally runs very rough when cold and I think it's running a bit rougher than it was a year ago.

First thing you need to stay above 10psi at the injector pump input port. After that your starving the injector pump for fuel and lube and cooling it.

What is your fuel pressure doing when your driving it like above.

I know if mine goes below 10psi it falls on it face.

Have you tried changing your fuel filter. You would be suprized. How many problems are caused by a dirty filter.

I have to argee, have them pop tested sound like that could be causing the problem... I've got stage 3 nozzles in my 99, I'm quite happy with them though they are a little hot.....

First thing you need to stay above 10psi at the injector pump input port. After that your starving the injector pump for fuel and lube and cooling it.

What is your fuel pressure doing when your driving it like above.

I know if mine goes below 10psi it falls on it face.

Have you tried changing your fuel filter. You would be suprized. How many problems are caused by a dirty filter.

15 psi idle and about 10 psi under load.. there is nobody local that can check the injectors that i know of. i would like to have them done tho

15 psi idle and about 10 psi under load.. there is nobody local that can check the injectors that i know of. i would like to have them done tho

I'm betting you local Cat dealer can. I know we can check mechanical injectors at our shop. Alban Cat. See what they would charge. Explain what's going on there.

x4 on the pop test of your injectors and see if theres a cummins or cat dealer in town, they might be able to do it for you.

15 psi idle and about 10 psi under load.. there is nobody local that can check the injectors that i know of. i would like to have them done tho

So, you have no diesel shops in your area?

You should have had them checked when you put the nozzles in anyway.

If you truly don't have anybody in the area to check them, do yourself a favor and spend the $20-50 and build yourself an injector pop tester.

what you describe sounds exactly what was happening with my '01 6sp. Ive got Diesel Dynamics stage 3 injectors on it. I replaced the APPS unit with a used one from Fleabay. has been cool for about 2.5 years. Im still on my OG injector pump as well. It was happening right around 1700-1900 rpm everytime.

what you describe sounds exactly what was happening with my '01 6sp. Ive got Diesel Dynamics stage 3 injectors on it. I replaced the APPS unit with a used one from Fleabay. has been cool for about 2.5 years. Im still on my OG injector pump as well. It was happening right around 1700-1900 rpm everytime.

yeah, i was hopeing the apps would fix my problem too, but no luck for me..

So, you have no diesel shops in your area?

You should have had them checked when you put the nozzles in anyway.

If you truly don't have anybody in the area to check them, do yourself a favor and spend the $20-50 and build yourself an injector pop tester.

any links or tips on how to build a pop tester for the 24v injectors? building the tester would be easy for most injectors.
I have seen them built with a bottle jack, some gauges and a old line

except the 24v injectors dont have a threaded nut where the line goes on.... its just a machined fit that a tube goes into ( i dont know what it is called)

fuel pressure is way to low. stock lift pump? 10 psi should be a minimum under a load checked at the shcrader valve on the pump. lift pumps can deliver good volume w/o the needed pressure. i use a old one for pumping fluids such as tanks out. making a difference cause the edge is turned off is just because you're placing less fuel demand on it.

possible problems could be overflow valve or lift pump. once you fix that maybe you'll be lucky and not have to replace the vp pump. they can go out and not give a code. rare but it happens and it's a real gamble to replace vp w/o a code so no one wants to do it till everything else is replaced w/o a change.

i'd spend the money on a good lift pump such as a pure flow rapter or a fass. stock style can not keep up w/ a box let alone injectors too. use a obd2 port scanner to check codes if you haven't already. 1693 code using the key method could be set off from the edge.

fuel pressure is way to low. stock lift pump? 10 psi should be a minimum under a load checked at the shcrader valve on the pump. lift pumps can deliver good volume w/o the needed pressure. i use a old one for pumping fluids such as tanks out. making a difference cause the edge is turned off is just because you're placing less fuel demand on it.

possible problems could be overflow valve or lift pump. once you fix that maybe you'll be lucky and not have to replace the vp pump. they can go out and not give a code. rare but it happens and it's a real gamble to replace vp w/o a code so no one wants to do it till everything else is replaced w/o a change.

i'd spend the money on a good lift pump such as a pure flow rapter or a fass. stock style can not keep up w/ a box let alone injectors too. use a obd2 port scanner to check codes if you haven't already. 1693 code using the key method could be set off from the edge.

x2 With all those upgrades you at least need a FASS 150 lift pump so you don't kill your VP44. Like others said have your injectors pop tested and check your filter.

x2 With all those upgrades you at least need a FASS 150 lift pump so you don't kill your VP44. Like others said have your injectors pop tested and check your filter.

BS. just moving the stock lift pump closer to the tank is all you really need to do. Ive had my truck on a dyno a couple times. a crack over 400hp and my OG VP44 is still kickin. That FASS crap is a waste of money for 90% of the people that buy it. You really need to be moving large amounts of fuel to require a high dollar fuel delivery system. BUT, thats just my opinion:flipoff2:

BS. just moving the stock lift pump closer to the tank is all you really need to do. Ive had my truck on a dyno a couple times. a crack over 400hp and my OG VP44 is still kickin. That FASS crap is a waste of money for 90% of the people that buy it. You really need to be moving large amounts of fuel to require a high dollar fuel delivery system. BUT, thats just my opinion:flipoff2:

results from a dyno YAWN. dynos put very little load on a motor compared to the use that a diesel pu generally gets. if you want to trust that little carter pump for the cost of a new vp go for it. 400 hp on a stock lift pump ? what's your fuel pressure read wot w/ a trailer on ?

both fass and raptor (pure flow) have lifetime warranties so it's a one time buy. hell even move to the next truck you buy. seems like a good investment to me.

blah blah blah... dynos put very little load on a motor compared to the use that a diesel pu generally gets.

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WTF are talking about?? so loading a powertrain to the point that it wont accelerate and or start to drag RPM down isnt an accurate way to measure torque/HP? Alllllrighty then. Dragging a ~10k load up Hwy 80 in 5th gear im still seeing right around 10psi of fuel pressure. Ive had my truck long enough that i have a small fund set aside for when the VP finally craps out. but whatever, i obviously dont know what im talking about if i dont have a bling bling FASS system.

the only load you're getting from a dyno unless you put the brakes on is from the size of the rollers. which is not nearly as much as a loaded truck. even w/ 400hp i bet once you are up to speed you could drive through the brakes on the dyno . this is why people w/ large turbos or twins have as hard time getting there turbo/s to spool on a dyno and will not build as much boost on one as they do on the street.

really not trying to get in a pissing match w/ you. to me it doesn't make sense to put go through the effort of putting on another carter pump about $200 for the pump plus cost of extending fuel lines and electrical just to have something that really isn't any better. a fass or raptor is around $500 w/ a lifetime warranty and comes w/ everything to install it. you'd hardly see your fuel press. gauge move at wot. seems cheap when most vp-44 die do to insufficent lift pump press. and they cost about $1200 and +/- install depending on you're abilities and where it gives up at.

the only load you're getting from a dyno unless you put the brakes on is from the size of the rollers. which is not nearly as much as a loaded truck. even w/ 400hp i bet once you are up to speed you could drive through the brakes on the dyno . this is why people w/ large turbos or twins have as hard time getting there turbo/s to spool on a dyno and will not build as much boost on one as they do on the street.

I think you need to learn a bit more about chassis dynos and what is available for them.

I think you need to learn a bit more about chassis dynos and what is available for them.

"An inertia-type chassis dyno consists of two big heavy drums hooked up to a computer. The wheels of an automobile spin the dyno drums, and the computer measures the speed.

The computer calculates the acceleration of the dyno drums by continuous measurements of their speed and the time. If the surface of the drums spin from a speed of zero to a speed of 10 feet per second in one second, then their surface acceleration is 10 feet per second per second, or 10 ft/s2. "

yes there other types of dynos but this is the most common. the weight of the drum provides the resistance. am i missing something ?

yes there other types of dynos but this is the most common. the weight of the drum provides the resistance. am i missing something ?

The fact that many chassis dynos have the ability to apply a load similar to what the truck would actually see, which is what Fueler is talking about.

You are correct that some dynos only have the weight of the drum for the load. In the case of one of my buddy's dynos that would be approximately 2500 lbs. He primarily deals with race cars that are in that area for weight, so it really hasn't been that big of a deal to him. The guys who are mostly dealing with diesels on the other hand, usually have the ability to properly load the chassis to get the turbo(s) working and make power. A diesel on a dyno without the load capabilities would be absolutely worthless. You'd never get on the turbos without it.

I'm really not a fan of chassis dynos if you are looking for horsepower numbers or trying to measure gains from swapping parts. They can be a nice tool to use for tuning though, provided the operator is decent.

My whole point with this is that Fueler likely had enough of a load on his truck to show that the stock lift pump was capable of what he was asking it to do while he was on the dyno. I'm not necessarily a big fan of the lift pump that Cummins elected to use in this application, but I'm not a big fan of the FASS systems either. There are other, more reasonable options for trucks not making big power if you know what you want and what you're looking for.