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suggestions on modified 03 drivability problems.

2410 Views 18 Replies 6 Participants Last post by  8secondride
I'm trying to help a fellow 2003 SO owner. ya'll know how difficult it can be with an 03-04 truck. The truck is a semi-built Auto trans. Truck has a reman CP3, Air Dog lift system, AFE air intake, Smarty pod, and Bosch 150HP nozzles. The truck surges going down the road at a steady speed and a visible haze can be seen all the time in followers headlights. are the 150's too much for the stock turbo and it needs more air ?? If so, I understand the haze, but not the surge. thanx , crossy
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no gauges or anything? now would be a good time to have a RP gauge. 150's are big for a stock charger but not impossible to run.

who's reman'd cp3 is it?
I know he said he does have a an RP gauge and that he has pressure turned down. I'm Not real sure what that means.
Sounds like he's referring to the pressure from the AirDog……IMO 150's are way to big for a 341...
well it comes back to my original question then I guess, will too big an injector make it surge going down the road? I know it would def make it haze. thanx, crossy
Is it surging just everyday cruising or surging while held to the floor? The % over of his CP3 would be helpful….I am assuming he's draining his rail
Any cummins especially with bigger injectors will haze….
found out it is a stock reman CP3- no surging when to the floor just cruising, steady RPM. thanx for the help, Crossy
Surging while in cruise control?

Sent from App
No, at steady speed. as far as the cruise control -I don't think he ever uses his. But MY 03 on the other hand does do a slight surge on cruise control and I was told that is the smarty JR doing that, but we'll stick to his issues. thanx , crossy
150's on a stock

That won't cause it to surge though. First place to start is rail, I'm going to guess it's fluctuating a good bit while surging. Not sure I've heard of the FCA causing surging, but maybe swap his with yours and see if that makes any change.

Rail sensor too maybe? He's lucky you have your truck, swap both those and see what happens. Pretty quick/easy to do.
don't make me look up FCA, never ran into that acronym. lol , Crossy
Did you have the nozzles/injectors tested when they were installed?
he said No, , because they were new.
FYI- I run YOUR injectors in my 1st gens. they are soooo simple & cheap compared to 3rd gens. lol
Its a good idea to have nozzles installed and calibrated on a test bench to verify things are right before putting them in. Most times there is not a problem.

mechanical injectors are easier to work on for sure.
don't make me look up FCA, never ran into that acronym. lol , Crossy
FCA=Fuel Control Actuator. It's the electrical sensor on the back side of the CP3
My 03 does the same thing you are describing. The cruise control surges like no other because of it being vacuum controlled, but I have figured out if I turn my POD down to around 65 or so it will cruise like normal. It also surges real bad at 2000 rpm which is right at 75-76 mph (which I like to drive alot). My rail pressure gauge will bounce around about 3000 psi sometimes but will average about a 2000 psi change. I finally took a video of it on my way home yesterday to show people. I'm pretty sure in my case it is due to a combination of my Arson III kit (modified FCA) and smarty programming. For me it ONLY surges within a hundred rpm's of 2000 rpm and is smooth all other times. Been this way for a while, just trying to save up for twin pumps so I can put the stock FCA back on there.
OK, so he brought the truck by today and showed me his turbo has noticeable play in the turbine wheel. I say if you feel it , it’s too much and you can really feel this. NOT touching housing YET. Anyway, I forgot that the 03-04 SO used the 341 not 351 so his turbo is REALLY small for the 150 injectors. My question is will a HE351 bolt right in place or are there notable changes that would have to be dealt with. He is tight on $ right now and getting ready for a long trip(empty- for now) and I suggested he at least attend to the stock one or find a 351 to bolt on. Considering his boost and Mileage is over 300K, he should expect to have some issues by now. I have some 40 hp tips that I told him I would LEND to see if it solves issues and maybe better MPG. Thanx, crossy

FYI- he also installed a rail return block off - no difference.
friends dont let friends they want to keep around borrow injector parts.
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