WOT fueling issues 2004 Drag Truck

[Dynomite]

Hey there. I have a 2004 Dodge Ram 5.7 Hemi that is solely used as a drag truck. Stock internals, 90mm TB, shorty headers, open exhaust and 150hp dry shot of nitrous.

I'm having an issue on the shifts from 1-2 and 2-3 where I get a lean spike in the AFR and then it seems to take a second or more to recover. My injector duty cycle drops from 80% to 60% during this time as well. Timing is flat at 19*, my PE table is the same across the board, and throttle stays at 85%. I don't run torque management so i'm not sure what is causing the fuel to change on the shifts.

I've attached the tune that's currently in the truck. Please keep in mind that this is strictly a drag truck. If someone has any insight it would be most appreciated.

Thanks

Kevin

infhemi -june 2021 tune 16 - Final run.hpt

[Dynomite]

Is it possibly a limitation with the transmission that I dont have control over with the 2004 PCM? Is it possible to swap to a 2008 PCM which has much more trans tunability?

[rchelicopter67]

Hello,
I have a 2004 Ram 1500 with 5.7 and i do not believe there is any way to disable the torque management settings. My engine behaves the same way pulling fuel while shifting.

Mark

[fast69mopar]

Is it possibly a limitation with the transmission that I dont have control over with the 2004 PCM? Is it possible to swap to a 2008 PCM which has much more trans tunability?

If this is a drag truck only then there is no reason as to why you should not switch to the later PCM. You only need the PCM to run the engine and transmission. You don't need it to communicate with any other modules if you have any left on the truck. I'd make the switch again in a heartbeat if I was not already.

When I switched from the 2004 model NGC3 PCM to the later 2007+ NGC4 PCM I went salvage yarding and found a donor truck and grabbed every single module and wiring harness I could get. I even took a mechanic friend with me so he could work in the opposite side of the truck as me and not have to ask a bunch of questions about how to do it or what to take.

I actually run a 2011 PCM in my 2004 Ram 1500 along with the TIPM, ABS, and instrument cluster. I swapped my instrument panel as well from the 3rd Gen to the 4th Gen. I got tired of not having any trans tuning options and I didn't want to run an aftermarket standalone system on this truck at the time so I found the cheapest donor truck and went to town. The 4th Gen interior is so much nicer too.

[drumnbasslvr]

Shot in the dark but try making FA Increase rate for Power enrichment 0.0100
Wish your tune also had Injector pulse width limit table.
Nos has its fueling separate from the pcm I imagine?
Super super rich can display false lean sometimes I've witnessed. You just might have to put the wideband in the exhaust stream closer to the headers collector, generally placement where the rear o2 would be and at least 3 feet of exhaust after the sensor.
Just firing off ideas.

[Dynomite]

If this is a drag truck only then there is no reason as to why you should not switch to the later PCM. You only need the PCM to run the engine and transmission. You don't need it to communicate with any other modules if you have any left on the truck. I'd make the switch again in a heartbeat if I was not already.

When I switched from the 2004 model NGC3 PCM to the later 2007+ NGC4 PCM I went salvage yarding and found a donor truck and grabbed every single module and wiring harness I could get. I even took a mechanic friend with me so he could work in the opposite side of the truck as me and not have to ask a bunch of questions about how to do it or what to take.

I actually run a 2011 PCM in my 2004 Ram 1500 along with the TIPM, ABS, and instrument cluster. I swapped my instrument panel as well from the 3rd Gen to the 4th Gen. I got tired of not having any trans tuning options and I didn't want to run an aftermarket standalone system on this truck at the time so I found the cheapest donor truck and went to town. The 4th Gen interior is so much nicer too.

Awesome! Thanks for the reply. I'm going to get on this! Did you have to disable SKIM to get it to work?

[Dynomite]

So I got a 2008 computer and put it in but I don't have any communication now. Dash says No Bus. Anyone have a solution for this?

[coanan]

So I got a 2008 computer and put it in but I don't have any communication now. Dash says No Bus. Anyone have a solution for this?

Does it require the vin to be programed in for the car to see it?

[spoolboy]

So I got a 2008 computer and put it in but I don't have any communication now. Dash says No Bus. Anyone have a solution for this?

Did you see the part where fast69mopar had to change a lot more than the pcm? The <05 trucks communicate on a different type of data bus than 05<. That means the instrument cluster, body computer, abs, etc won't communicate with the 08 PCM.

I think the important quote would be "every single module and wiring harness"

[fast69mopar]

So I got a 2008 computer and put it in but I don't have any communication now. Dash says No Bus. Anyone have a solution for this?

Sorry I didn't see your post. I didn't get a notification from the website for some reason. The 2002-2005 PCM's operate on the PCI Bus and the 2006-2008 PCM's operate on the CAN bus. I did have to have SKIM disabled in my PCM because one from a manual trans truck was not available. I did have my VIN programmed to my new PCM too. With the 2008 PCM in your truck the instrument cluster will show NO BUS because the two modules cannot speak to each other due to the different BUS strategies but it will not keep the truck from running as long as SKIM is disabled or the PCM never had the secret key data programmed.

Do you know the VIN from the donor vehicle? If so, we can find out if it has SKIM or not. I'd you have the donor truck available to you then you can grab the other modules and wiring to make this work the way you need it to.

Mainly to make this work for you you would need the PCM, TIPM, Instrument Cluster and some wiring along with some tuning. I apologize for my post not explaining these things.

Did your truck come equipped with SKIM? Black key or grey key?

[PurpleRam]

I know you state open exhaust, where's your O2s ? How much pipe are you running after the Shorties ?
What Injectors are you running ?
What Intake Manifold ? .......stock truck Intake ?
What Elevation is the track ?