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What tests are valid for injector replacement?

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FCA or Injectors?

47DE service

On my 05, 3500 Dually, I replaced the injectors based on a somewhat reputable, local shop's recommendation.

He said there return flow was 3x the maximum allowed.

I replaced the injectors, with no noticeable improvement in performance.

Truck has 140 +- on the clock.

It's always started no problem, and has decent hight end power, but sure can't pull out in to a tight gap in traffic.

It literally makes not one pound of boost until it hits 1250 RPMs, upon which it gets up and goes pretty well.

It runs a bit hot, and the heat then transfers into the transmission (fully high end rebuilt), which can't keep itself cool when the going gets tough, like on any unlocked hill climb, heaven forbid the stop and go traffic so common on Eisenhower pass.

I took it to another reputable (I think) local shop who has now said it needs a turbo (waste gate issues) as well as a head gasket AND new injectors.

I think he is using the same return flow test, along with the concept that individually shutting off each cylinder should have caused a larger drop in RPMs, he said they were all close in what each one dropped, and took this as a signal that they were all bad. Seems to me this could just as easily mean they are all good?

A third party claims there is no way to diagnose bad injectors on the truck, short of it having troubles starting, when it gets pretty obvious. Apparently the return flow needs very special equipment to be of any validity; simply measuring return flow is not adequate.

I really don't want to replace my brand new injectors based on the same potentially flawed test that may have condemned the original injectors prematurely.

What issues, turbo or other, could prevent the motor from making any boost below 1250 RPMs?

If the wastegate was to blame, it seems it wouldn't suddenly start making boost at 1250 rpm. It makes up to 32 psi @ WOT. Removing the wire to the waste gate actuator changed nothing.

If the turbo is unhealthy, is it worth considering a rebuild? I know a local shop in Denver that rebuilt both my injection pump and my turbo, on a Perkins diesel that runs well 15 years later.

Rail pressures seem to be in parameters.

Lastly how can I know if I really need a head gasket? There's no evidence of cross contamination. The tech said coolant was pressurized. It seems like the radiator cap would blow or there'd by coolant on the overflow; neither are evident. What pressure should the coolant be under? Is this worth buying a test cap for?

It blew an intercooler this spring. Could this be a clue to there being downstream restrictions between it and the motor?

Thanks for reading, and taking the time to help me make sense of this.

Dave
 
Ask him what part number special tool he is using to check the return flow? If he doesn't say Miller 9012 or equivalent he isn't checking it correctly. You have to isolate pump return from injector return and that requires the 9012.
A stock truck should NEVER need a head gasket unless someone did something really stupid like running without coolant for a while.
 
I have spent hrs on the Phone with OP, its NOT injectors, They are form TC .

The Shop at 3X time the Max....at that rate the CP3 would NOT produce enough volume at cranking to produce the minimum Pressure for the Pressure sensors to send signal to ECM to fire the hot hole.

Its not fuel related.

At this point the truck need to see someone with in-depth knowledge and tools, plus all the work-around.

It builds Boost at High Rpm's and it fuels good, it just does not do it at low Rpms

Here's My Guesses in order

1 Turbo
2 Valves or valve train.
3 Cam

It disgust Me how many shops that claim to be experts on Fuel Injection (HPCR) cannot answer the elementary questions when someone with in-depth Knowledge investigates the methods they use to condemn Injectors.
 
Why are you expecting boost at 1250 rpms? That is still on idle circuit and you will not get significant boost at that rpm, there is not enough fuel to create exhaust flow to spin the turbo and make boost.

Adequate fueling for making boost under 1600 rpms is not going to happen unless you ave a tuner and you reduce the fuel limiting maps. It should not matter anyway as the TC stall will allow the revs to jump up where there IS fueling and boost will jump, not immediately because that is not how a turbo works but it should be fast enough it isn't an issue.

What exactly are your trying to do that you feel is inadequate? Describe circumstances speed, AC on\off, ambient temps, etc. At a complete stop watch your rpms when you slap the throttle, DO NOT GO WOT! What do they flash to when you hit the throttle? Is your TC TU and causing it just dogg along until all of a sudden it jumps? Is the trans downshifting to 1st gear?

Last but no least, crimp the boost reference hose on the turbo to completely take the WG controller and its programming out of the equation. Does that change anything in low rpms? What will boost max out at then? You see mid to high 30's and will probbaly toss a CEL if you have stock tuning but at least you will know if the turbo is working correctly.

From just the bas einformation you have posted it sounds more like a transmission failure and\or trans tuning problem, coupled with stock engine tuning.
 
The Turbo makes boost at 2000+ Rpms, it just NOT making normal boost under load at lower Rpms, Its My understanding he has other 5.9s to compare.
 
The expectation of more than 1 or 2 lbs of boost under 1200 or even 1500 rpms is incorrect, there is not enough fuel to generate exhaust flow to make boost. The engine needs to flash to at least 1800 rpms to push boost into a decent rise, if rpms do NOT flash to at least 1800 when the throttle is stabbed the something is interfering with normal operation, incorrect stall in the TC or TC has failed or CAC is heat soaked or something else not thought of.

If he can see rpms slowly rise to 1250 then take off there is a problem somewhere, should never see that.
 
Thanks guys. I do have the Edge insight and available power mapping, but it is set to zero.

I know some love soot, but I couldn't use it in higher modes!

My problems are two: lag to get started, and higher than expected engine temps.

My expectation are based primarily on our '03 that I've put 240K on since purchasing it brand new.

That truck accelerates like a sports car, compared to the unloaded dually.

I'll look more closely at how the lower RPM boost develops.

If we decide these are all normal parameters, I just need to mitigate some excess heat to keep it away form my transmission.

transmission guy suggested adding a bypass cooler for the engine as being more helpful than added trans cooler, which helps only unit it gets hot, then does next to nothing.
 
He did the test correctly at load, Its somewhat of a nasty way to do it but in extreme Cases like this one ,I gave him the procedure.

AE it did have a leak and the CAC was replaced with New
 
03 and 05 will run differently, and build boost differently.

What are the high coolant temps?

Remove any wiring harness for the Edge from the truck, aside from the OBDII for the monitor.
 
If I were to climb in stop and go they quickly ht 220, if it goes on for an hour it would be more than 260. this was one of two factors that led me to rebuild transmission. Lower temps did not accompany rebuild.

On a zero degree morning, climbing 6 % grade loaded with 5Klbs, with no traffic but windy mountain roads doing sub 30 miles an hour is still hits 230F.

Maybe the boost parameters are normal or at least way closer than I thought. It is just way too sluggish off the line to be normal!
 
If I were to climb in stop and go they quickly ht 220, if it goes on for an hour it would be more than 260. this was one of two factors that led me to rebuild transmission. Lower temps did not accompany rebuild.

On a zero degree morning, climbing 6 % grade loaded with 5Klbs, with no traffic but windy mountain roads doing sub 30 miles an hour is still hits 230F.

Maybe the boost parameters are normal or at least way closer than I thought. It is just way too sluggish off the line to be normal!

Are those trans or coolant temps?
 
You cannot run these transmissions in stop and go traffic in summer temps loaded and NOT hit 260 degrees without an additional cooler or using a lockup switch, not enough air flow to counter heat generated by the TC.

On a grade with a load and sub 30 mph you need to be locked up in 2nd or you will see high trans temps. Has nothing to do with engine coolant temps, it is all in the transmission and fluid coupling.

At speed where the TC can lock even in summer temps trans temps should be 200 or lower. If not you likely have transmission issues, it is slipping.
 
AH, I am less sure than I should be. a lot of what I was worried about was how much higher her EGTS are than the '03, but several folks assure me this is normal for this year, as lame as that sounds.

Engine temps as trans starts overheating may have been around 205? would shaving degrees off of that with the Fleece Bypass cooler do much for transmission temps? Seems like it would best only a drop in the bucket.
 
Thanks Cerb. Per our transmission threads a year or two back, I have the Copilot and Od lock out and do everything I know how to do to try to hold TC locked up for all climbs. The one referenced is the 3 steep miles up to Buffalo pass, from Steamboat.
 
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