3.9 to 5.9 magnum swap in my 2000 Dodge Dakota

[axisg]

hmmm. sounds like you have some troubleshooting. If its running on all 8 why is it throwing codes for cyl 7&8 ? How do the plugs look ?

Are you running the orig 3.9 PCM or the updated one you mentioned ?

Would be great if you could get one from an R/T and bypass the security just to rule the ECM out of the equation.

 

[olds307 and 403]

I had an R/T computer, had issues B&G ended up using my 3.9 computer. Trust me, I ran my truck with the 3.9 computer, ran awful, would barely idle. This fired up in -10C no problem, idled smooth and revs fine. I think the problem may be found. After searching for pinched, melted or frayed wires and everything looked good. I looked the C2 connector wiring diagram. It not only houses the injector driver wires, it holds all the trans wiring. I had to pull it apart to add the #7 and #8 injector wires, thinking they are not seated properly, I will be pulling it apart again. I had 0 trans issues other than resetting the TV cable before the swap.

 

[olds307 and 403]

I checked the pins in the connector, everything is where it should be. I am buying the complete solenoid kit and replacing it harness and all. I just changed the TCC/OD solenoid but not the wiring, that will be changed too. I may have pinched a wire setting the front band or installing the 5.9 motor, so I will check for opens between the ECM and trans connection. I had the same trans code between 2 different ECM's, so highly doubt it is that. The R/T computer ran just long enough to set that code.

 

[olds307 and 403]

Solenoid kit should be here this week. I am only running on 6cyl, pulled the connectors and hooked up na noid light nothing on 7 and 8, nice pulse on #5 injector. I will have to triple check but I am pretty sure the pins are in #2 and 13 on connector 2 like they are supposed to be. Strange indeed.

 

[axisg]

keep plugging at it and you will get there. I had a 95 neon for 9 years and over 600 thousand kms that we would run the Toronto Montreal corridor for years so I can recall quite vividly how fussy these PCM and BCMs are. Wish you were closer as I have a DRBIII that would probably help you out. Sometimes a harness swap is easier than trying to trace down a break or even worse an incomplete connection with a pinched wire or bad ground.

 

[olds307 and 403]

I am going to check for voltage on the green/orange wire and do a resistance check from the injector plug to the connection to the computer for #7 and #8. It actually runs quite smooth on 6 cylinders since B&G did the tune. I will actually be OK if the trans starts shifting through all the gears. Everyone says how easy this swap is, not for this guy. Seems all my vehicles hate me lately and one even committed suicide.

 

[olds307 and 403]

Well both head gaskets got blown out of it when my daughter over heated it. The plenum gasket was starting to go as well. I am splicing and soldering from the #1 and #5 injectors to fire #7 and #8 injectors and using male and female spade heat shrink connections to run on 6 cylinders around town if i want. I finally got it all apart and I am cleaning everything up. No obivious cracks, which is good for these magnum cylinder heads. Should have it going next weekend.

 

[olds307 and 403]

Well I finally used chewing gum and bail wire to get this thing working right. The head gaskets are holding great, flushed the cooling system and oil and jumped the extra two injectors. Ran better all around, could lightly spin the tires with only second and third due to limp mode. I spliced into the the converter and OD wiring with a toggle switch to ground. I also jumped the relay with a heavy wire, found someone who did it. I instantly had all gears except OD (works with toggle switch) and wheel spin so hard it was hopping. I also added a really big trans cooler that is supposed to bypass when cold. Finally not a turd, especially with the 5000 rpm plus shift points in the recalibration. I just needs the command start working and winter front to finish this truck.

 

[olds307 and 403]

This truck runs really well with the bypass on the trans relay and has OD with a toggle switch. It has all the power back since the battery died. Nice smooth idle again and moves quickly. I will be taking it to then track on Sept 3 down the 1/8 mile. I will be tickled with a 9.6 in the 1/8. There is a better tune, air filter, air box opening and a deeper first gear than a R/T but more weight. Traction will be the biggest issue.

 

[foxtrot]

This truck runs really well with the bypass on the trans relay and has OD with a toggle switch. It has all the power back since the battery died. Nice smooth idle again and moves quickly. I will be taking it to then track on Sept 3 down the 1/8 mile. I will be tickled with a 9.6 in the 1/8. There is a better tune, air filter, air box opening and a deeper first gear than a R/T but more weight. Traction will be the biggest issue.

Nice! Why do I hear the 1/8 mile track mentioned in CA so much? Here I the states we talk about the 1/4 mile track mostly..