04.5 or 05 ECM on an 03?

[BHaner]

Truck is an 03. 5, 6 speed, dual APPS.



Anyone ever tried to run an 04. 5 or 05 6 speed ECM?



Tired of being held back by the 03 programming. Looking to try something else...

 

[Matt400]

Sounds like a can of worms, for an example the 03 coolant temp sensor is different than the 04-

The 04's ECM has different software to recognize the updated sensor which not only runs the gauge but fan clutch too.

Sure, you could install matching ECM & CTS but that is just one thing I know of so there may be other differences lurking in the swap.

 

[BHaner]

So I would need a fan clutch from an 05, and a temp sensor?



Hmm.



Talking with Bob W / Marco now to see what might work.

 

[Matt400]

I cant say about the fan clutch, just that the ECM controls the fan clutch based on CTS inputs. You would need a CTS from the same year ECM.



Say for example you want to use an 04. 5 ECM-

A good idea would be to make a list of all the sensors the ECM looks at for inputs on your 03 and then take that list to a good DC parts man to make sure the list of sensors have the same part number as that same list of sensors on an 04. 5

 

[Lightman]

Another thing to think about is the third injection event and how the injectors are controled

 

[BHaner]

Another thing to think about is the third injection event and how the injectors are controled

I think that extra injection event may be where some of the power comes from... But hard to say!



Gonna give it a try. See what happens.



Anyone have a spare 04. 5 or 05 ECM sitting around? Any will do.

 

[Matt400]

Another thing to think about is the third injection event and how the injectors are controled

True. . and I think the injectors are different part numbers so they are going to be matched with the ECM.

 

[Lightman]

True. . and I think the injectors are different part numbers so they are going to be matched with the ECM.

The only thing different is the tips the 03-04 305/555 have 8 holes and the spray angle is different, the injector bodys will interchange

 

[BHaner]

Yeah. The ECM should not be able to tell the injectors are different.



I want to keep the 03 injectors because they are made to match the pistons that I have.

 

[Matt400]

Yeah. The ECM should not be able to tell the injectors are different.

No it wouldn't, but where you begin to guess on the match up is the fuel flow between them.



Speaking in theory only here cuz I don't know the flow difference if any,

but what if the 03 injector tips have smaller holes- the matching 03 ECM is loaded with software to flow X amount through them.

If the 04. 5+ tips have larger or more holes (flow more) the engineers are able to cut the fueling software command back from what was required in 03.



In that scenario you would have less power with a newer ECM as it commands the injector on time less based on larger or more holes.



Thats just me thinking about the can of worms comment I made earlier but I am sure someone will know what the flow rates are for the various years.

 

[cerberusiam]

IF you could get the ECU to work without the peripheral inputs it needs, a big hassle as the later trucks have 6 or 7 smaller units feeding the ECU, the fueling parameters would more than likely burn the motor down in a very short time.



There are significant changes in timing, cam profiles, valve timing and overlap in the 04. 5+ engines. You can't compensate without major hard part changes or a program change. The power and TQ of the later engines is not only ECU programming.



The 305 engines are capable 500 HP with stock injectors and well over 600 HP with upgrades. Why not work with what you have and enhance it? If you crave really big HP, P-pump it.

 

[BHaner]

IF you could get the ECU to work without the peripheral inputs it needs, a big hassle as the later trucks have 6 or 7 smaller units feeding the ECU.

Did a test today. 05 6 speed ECM. Got the following codes. Would start and run for a second. Then shut down.



0242 - Wastegate Pressure Control (It can't see the 04. 5+ electronic wastegate because I don't have one)



0628 - Low Voltage at fuel lift pump (it can't see the in tank pump I guess)



0477 - Engine Brake Driver Low (No idea on this one. 05 Did have a pacbrake)



0118 - Coolant Temp Sensor Voltage High (see above about this one)



2127 - APPS Circit 2 Low Voltage

2122 - APPS Circit 1 Low Voltage (Must be the same situation as the coolant temp sensor, would need an APPS from an 05)

 

[BHaner]

the fueling parameters would more than likely burn the motor down in a very short time.



There are significant changes in timing, cam profiles, valve timing and overlap in the 04. 5+ engines. You can't compensate without major hard part changes or a program change. The power and TQ of the later engines is not only ECU programming.

Fact of the matter is, when I have the smarty loaded, TST on, and the EZ on... Not much of the factory parameters are doing anything anyway. So, doubt that would matter.



As for the cam profiles, valve timing, and overlap. . That may be true for the stock cams. . But I am running an aftermarket F1 Cam. Same cam for 98. 5-07. So thats not going to matter either.



The only parts I can't change would be the pistons and injector tips. Even then, if I wanted to dig in deep. . Wouldn't take much to match those too.

 

[BHaner]

The 305 engines are capable 500 HP with stock injectors and well over 600 HP with upgrades. Why not work with what you have and enhance it? If you crave really big HP, P-pump it.

True. But how many actually made 500 with stock injectors? Not many that I know of!



I know I was not able to get over 430 without an injector change.



Took alot of upgrades just to hit 600!



I have worked on this truck for over 3 years now. I have sucked up as much info as I could. Changed every part from the fuel in the tank to the tip of the injector. Still... Low numbers.



I have taken the head off, checked everything there. . Pistons and walls looked great! Head had some minor cracks around the valve seats. . But nothing major. valves sealed fine.



I have had two different twin sets. Also, two different top turbos on the current set. Still, low numbers.



I have narrowed it down to an electronic issue at this point... But still not sure what way to go.



I guess mine is just one of the ones that doesn't want to make power.



As for the P-Pump... That would be a big step backwards if you ask me. If I wanted to build a 12 valve I would have. Seems like everybody and their dog has done it.



I guess I have two choices at this point. . Keep looking for a solution to the problem the truck is having. . Or start over with another truck.

 

[sag2]

Be very careful when swapping ECU's. Don't know where you got the 05, but if your truck has SKIM key and the 05 does not, you just ruined a $1200 05 ECU. SKIM is learned, and once learned you can not change it back to non SKIM. The other reason it might have started and died is if the 05 ECU had SKIM and your truck does not. Until the 05 ECU sees a SKIM code from the WCM it will start and die, then not crank after about five start attempts. If you have the VIN of the truck the 05 ECU came out of we can see if it has SKIM or not.

 

[BHaner]

Yep! Your right!



The 05 has a SKIM key.



My 03 does not.



That would explain the start, then stop issue.



Guess I need to find one without.



I might also see if I can find an APPS and coolant temp sensor.



Would be neat if it worked and solved some of the issues I am having.





Both trucks are back up and running fine at this time. Maybe I should just quit while I am ahead. lol

 

[Bob Wagner]

byron, you guys are playing with fire :-laf

 

[BHaner]

It's all good!