Motorcraft CM5058 vs. CM5138. Anyone know why the 05' specs a different injector for a 5.4 non heritage? I put in CM5138 into an 04' and I'm getting a LTFT Rich condition making me thing they are bigger

 

I did the same thing and got the exact same results, Don't know why it would make a difference???? 5.4 3-Valve are the same motor. My only conclusion was that the PCM Flash level is different and Ford changed it due to problems "burning out" 2004 due to an over lean condition. If the PCM is re-flashed with an update version would that help?

 

Why would you want to run an 05 injector in a 04? Why not use what it calls for?

 

The 2005 injector is about 25% of the cost of the 2004 injector.

 

I guess I could see the want for savings but the 2005 injectors are crap. After the first one failed in my 05 and my truck still having misfire issues I went ahead and replaced all of them thinking I wouldn't have any more issue with it. After spending the money on the new injectors and installing them I still had another one fail. The second one that failed burned up my convertor and I had to have my truck towed to the dealer because I did not want to try to start it and hydrolock my engine.

If you want my opinion, spend the money and install the 04 injectors. It will be cheaper than a new engine

 

I selected 05' injectors because as an 04' owner I'm tired of getting "Heritage" 2004 F150 parts (previous body style) from vendors who don't have that distinction in their ordering system. I didn't even know the 05's were cheaper, OR different. In the end, they are probably 21lb or 24lb/hr injectors and the 04' is probably a 19lb injector. They are both made by Bosch or Siemens so SHOULD be high quality. If a tuner wanted to take the time (and I was willing to pay) I could get a custom tune to map/rescale my MAF to these injectors but the price would exceed the cost of just going to the proper injector.

I am getting OEM refurb's from RockAuto. I tried to have mine refurb'd at a local shop here in Dallas that does injector rebuilds but they said they don't have the fitting necessary to clamp to these units and couldn't do it, and the maker of their injector testing machine doesn't even sell the fitting.

Scooterdog, what are you referring to here: "problems "burning out" 2004 due to an over lean condition."??
What is the 2004 lean

 

JerryK i'm with you 100% on the 2004 Heritage parts. So many computer systems have my vehicle with a EGR system, IAC, and many other non 3 valve motor sensors, i'm sick of getting the wrong parts and having to pay to ship them back!

Lean condition: When the 3 valve motor was launched in late 2003, they didn't have great long term data on the affect of running a motor so lean. I get better real life gas mileage with my 2004 than my brother with his 2005, but at a cost. Many techs talk about the 3 Valve runs too lean and can cause piston, ring or valve failure. My guess is that Ford started seeing some data in mid 2004 that pointed to an over lean condition and hence did a major change in the injector (and flow data in the ECM) for the 2005 model year. Too bad the injector change also caused a major quality problem with sticking injectors. Another guess is that Ford rushed the higher flow injectors into production and didn't get the longevity and quality testing finished.

I still look in the "2005" section of most part suppliers for anything I need on my 2004, but Injectors don't transfer.

 

Hmmm good info thanks Scooterdog, that could explain why inhale a possible burned valve or two. I'm hoping it's just sludge that a half bottle of sea foam in the intake cleans up! I got a new refurb motor in 06 or 07 due to rod knock, too bad they didn't retrofit my injectors at that time.