Hey guys, question for you:

Im putting together a truck, from a few different year model trucks, and had a question about the ECM working with the injectors.

What it is, is an '03 model CR HO (305/555) CTD, and the ECM/wiring harness is what I THINK an '04.5, however, it MIGHT be an '04 ECM/wiring.

Let me explain why I think it's 04.5, and you guys can correct me if Im wrong (PLEASE do so!!!!)

I know on the '03's, that they have 2 "computers" (ECM and PCM) if the truck is an automatic.....1 for the CTD and 1 for the auto transmission.
I was under the impression, that the '04's were setup like the '03's, and had 2 "computers" as well, again, 1 for the engine, and 1 for the auto transmission.

I was also under the impression, that the '04.5's went to 1 "computer", that controls both the engine and auto trans.

Now, I KNOW this motor/injectors/etc... is an '03 model.
The "computer" is what Im questioning....what year it is, and if it will work with the '03 motor/injectors.
It only has the 1 ECM, and the wiring harness is from the same truck that the ECM came from. The "Date of Manufacturer" on the truck that the ECM/wiring harness came out of (door jamb sticker), says it was built in Jan '04.


So, guys, I guess my question is as follows:
1)Do we know when the cutoff date for the '04/04.5 was (what date is used to determine if it's an '04, or an '04.5?)
2)If the ECM/wiring is in fact, out of an '04.5, will it work with the '03 engine/injectors? I am DOUBTING that it will, just wanted to be sure, and ask you guys.
3)If the ECM IS an '04.5, and WON'T work with the '03 motor/injectors...what would it take for the '04.5 ECM to work with the '03 motor? Just swap over to '04.5 injectors? Or is there more work involved.

Thanks guys for the info/answers....sorry for the long winded post!!!
2)

 

I don't know anything about the compatibility of the 04.5 harness to 03 guts, but the 01/2004 date does indicate an 04.5. All early 04 models were manufactured in calendar year 2003 and did not require a catalytic converter to achieve EPA standards. On January 1, 2004 the HO got a bigger turbo and a catalytic converter to comply with EPA standards, and the 04.5s were born.

There's at least 10 threads on the subject. The only reason I know is because I went and bought an 04, then I found this site and read everything I could about them. As luck would have it, I got one without the catalytic converter and other than a fuel pump failure, I have not had any major operational issues.

Good luck with the rest of your questions. My logic says that if all the connectors are compatible, then the system would be compatible. The 04.5 ECM would probably need to monitor an O2 sensor because it should be thinking it has a catalytic converter, so maybe a delete kit could overcome that. How hard is it to find an 03 ECM and wiring harness? It might save you some heartache to be patient and go like with like, especially on the electrical system part.

 

As was mentioned, the truck's door jamb manufactured date of Jan 1, 2004 was the cut over date from 2004 to 2004.5.
The actual 2004.5 engines will have an earlier date. My original engine is dated Nov 2004 in my 2004.5 truck manufactured in Feb 2004.

I've found that the quickest way to tell a 2004 truck from a 2004.5 is from where the coolant overflow tank is. Dodge moved it from the drivers side near the radiator to the passenger side firewall for 2004.5.
Cat's, turbo's, exhausts can all be easily swapped on these trucks now that they are getting up there in years.

The only difference between a 2003-04 injector and a 2004.5-07 injector is the nozzle. 2003-04 engines had different pistons and nozzles than 2004.5-07 engines.
The injector nozzles must match the pistons.
The injectors can be swapped between engines and between ECU's.

Not sure what you are up to but it's normally best to just swap engines and injectors for the 2003-2005 trucks, keeping the ECU and engine harness that was originally in the truck.

ie. The 2003-04 ECU and harness will run a 2004.5-07 engine and injectors just fine.
The 2004.5-07 ECU and harness will run a 2003-04 engine and injectors just fine.
Note that Dodge changed the valve cover design and injector harness in 2006 just to add confusion.


If you are mixing and matching parts:

The 2003-04 ECU will provide better fuel mileage but less features and aftermarket support than the 2004.5-05 ECU.
The 2003-04 cylinder head is not as reliable as the 2004.5-07 head.
The 2003-04 pistons are superior to the 2004.5-07 pistons.
The 2004.5-07 turbo is very small and has an electronic wastegate.
The 2003-04 turbo is even smaller, old school strictly mechanical wastegate.

I hope this info helps!

 

Guys, MUCH appreciated with all the info. The "bad" thing in some of the things to look for, under hood, like coolant bottle, won't help me unfortunately. The truck's motor, and ALL accessories/bottles/wiring, were gone before I started on the truck.
However, that being said....with info that was given from above, I can pretty much say the ECM is an 04.5. The truck had a catalytic converter on it, and it only has the one ECM (instead of 2, on the 03-04 auto's).

I was able to get the truck fired up and running, but I've got a check engine light, and it surges a little bit.
I didn't get a chance to run the diagnostics yet, but I also haven't hooked up the 02 sensor yet either.
I was curious to see if it would run. LUCKILY I had the steering column/key/ignition switch from the donor ECM truck.
At first, I had ECM (again, '04.5) hooked up to the '03 motor and it wouldn't start.
It would crank, but not fire off. I took ignition cylinder/key out of donor ECM truck/steering column, and put it in place of the '03 ignition/key, and she popped off.
I only let it run for a few seconds, as again, I didn't have a number of items hooked up.
But, she DOES start, and she DOES run.

I'll have more of an update first part of this coming week, and let you guys know how she's doing and if I have any problems/questions.

Thanks for the info and detailed reply...again, MUCH appreciated!

 

The main thing is to match the injector nozzles with the right motor. In other words a 04 down motor will need those nozzles to kepp fro melting the motor and vise versa on the 04.5 up. We have used 03 injector body in a 07 and it ran fine, the only thing we did was put the correct nozzle on it.

 

That wont be a problem, as the only thing that was changed was the actual ECM itself.

The motor, from valve cover to oil pan, from turbo to intake, from injectors to CP3, is all '03 305/555 stuff. Basically took that motor (which was in front of a NV5600) and shoved a 48RE behind it, changed computer/wiring harness and presto change-o....

What was throwing me for the loop was if the 04.5 computer (not to mention...was it an 04 or 04.5) would actually work with the '03 injectors/motor.
I wasn't aware of the ACTUAL differences in injectors/electronics....and just thought there was a possibitly, the ECM wouldn't operate the injectors.
I didn't realize the only main difference was the nozzle.

Thanks for the reply.

 

OK guys, I AM going to have some more questions, about location of some pigtails and what they attach to/plug into.

I'll get some pics up later, but so far, I have found two pigtails, on this '04.5 wiring harness, that there is nothing to plug into, on the '03 motor.

One is off of the harness that drops down to the AC compressor. There are 3 pigtails, 1 for the compressor, 1 for the high side pressure switch, and 1 for the????? Again, I'll get pics up later.

The other one so far, is on the drivers side motor, and a rather large pigtail...6 pin connector, and drops down close to front of the motor.
I am not familiar with the '04.5 Vis Clutch Fan, and it's pigtail...so maybe that is what this harness is for? On the '03, the pigtail came out on passenger side of radiator, and this one is on the drivers side of motor.
Again, I'll get pics up...but maybe you guys already have an idea on what the '04.5 up has, that the '03 doesn't????

Im THINKING that the harness on passenger side motor (down by AC) is for o2 sensor, BUT, that pigtail is pretty close to front of the motor, is why Im thinking it may not be.

Pics later on, thanks guys.

 

OK guys there are 3 pigtails Im curious about.

1st one:
Its located off harness that drops down to AC compressor. There are 2 pigtails for AC system...1 goes to compressor, other goes to high pressure switch. The pigtail by my pinkie, is the one Im curious about. It's a 2 wire connector:




The second one, is the 6 pin connector (grey connector, next to my thumb) As you can see, it drops down right next to Cam and Crank sensor:




The 3rd one, drops down by drivers side headlight/fog light area (but all of those items are plugged in. It's a 4 pin connector, here are two views of it:






So, you guys think you can help me out?

 

Bump for the morning crew....

 

My truck has build date 7-2004 for chassis and engine.

The 2 wire on your pinky goes to my turbo wastegate, the 6 wire goes to my elec. fan clutch. I am looking for the other.....

 

I do not see the 4 pin plug. My truck does not have fog lights. Maybe that's it??? I do see a small 2 pin plug in my bumper that is on left side and nothing plugged into it?

 

OK, figured out what the grey 6 pin connector is for...that is for the elec fan clutch. I ran down to local parts house, and they pulled out the fan clutch for the '04 and it matched up with the pigtail/wiring harness.
So, that solves that.


1 down, 2 to go.

Still need to find out what the other pig tail on drivers side (by the head lights) is for, and the 2 pin connector down by AC compressor/turbo is for.


What about vacuum pump? This '03 motor doesn't have one...did the '04.5 have a vacuum pump...and that is what one of these pigtails plug into?

 

Awesome! Didn't even cross my mind about the waste gate. That ought to be interesting, since I have the '03 turbo. I guess we will find out what computer does if I leave that unplugged.


The 2 pin you are talking about...yeah, I know what that is...I've got that as well. The 4 pin though, def not fog lights...that's plugged in. Vacuum pump?

Thanks for your help dragonslayer!

 

Along the way, I have also found out that the Coolant Temp Sensor is different between year model trucks, AND the wiper motor as well. Just a little FYI in case anyone was wondering. Everything else seems to have found a home so far, EXCEPT for the 4 pin, on drivers side, down by head lights/fog lights.

The only thing I can think of right now, is the vacuum pump.

Thanks to Dragonslayer, we were able to determine the 2 pin was for wastegate, and 6 pin was for the elec clutch fan.

Thanks again Dragonslayer!

 

no vacuum pump on those motors when ya find out what happens by leaving the wastegate solenoid unplugged other then the cel being on keep us posted lol