billetgrey
Junior Member
Tl;dr: fired up truck post lifter+cam swap. Runs great but has a P3425 "cyl4 deactivation control circuit" code.
Hey guys. I just finished buttoning everything together on my Hemi and refilled fluids. I made sure the battery is in good shape since it wasn't used or charged for a few months as my charger took a **** last summer. It had 12.5~ volts, verified by my multimeter. I also used another vehicle to boost it while I cranked a few times with the fuel pump fuse pulled. So I am pretty certain the battery is good.
First time I started it, it was quite noisy-mostly due to the driver side exhaust pipe to manifold leaking kinda bad and visibly. I let it run regardless for about 10 minutes and it otherwise sounded and ran nice and strong. It had a check engine light on however:
P3425-Cylinder 4 Deactivation Control Circuit
After shutting it off, I tried to clear it with my scanner, in run mode with engine off of course. But it instantly came back. I still had the misfire code from before the repair leftover and that one went away and hasn't come back, so I know the scanner is functioning and is interfacing properly with the vehicles electronics.
Anyways I started it up again and it again ran nice, but this time also sounded brand new with the exhaust properly fastened. But the code was still present. I drove around the ranch a bit after keeping the throttle at about 2000rpms for another 10ish minutes and it drove like normal.
Right now I'm taking a break, I disconnected the battery to see if that changes things. While the heads were off way back when, I checked to make sure I put the reg and MDS lifters in their right spots, and double checked like dozens of times before I put the heads back on, lol, so im certain they're in the right spots. Is there anywhere else in the wiring I should look? Is there a certain plug I may have missed? Any other way I could troubleshoot?
I should say a massive thank you to this forum and the active members. I was quite confident going into this repair but ran into many hurdles otw and took quite a bit longer and many more sessions than I foresaw. It's really because of this forum that I am like 99% successful so far. I really appreciate all of the support.
Hey guys. I just finished buttoning everything together on my Hemi and refilled fluids. I made sure the battery is in good shape since it wasn't used or charged for a few months as my charger took a **** last summer. It had 12.5~ volts, verified by my multimeter. I also used another vehicle to boost it while I cranked a few times with the fuel pump fuse pulled. So I am pretty certain the battery is good.
First time I started it, it was quite noisy-mostly due to the driver side exhaust pipe to manifold leaking kinda bad and visibly. I let it run regardless for about 10 minutes and it otherwise sounded and ran nice and strong. It had a check engine light on however:
P3425-Cylinder 4 Deactivation Control Circuit
After shutting it off, I tried to clear it with my scanner, in run mode with engine off of course. But it instantly came back. I still had the misfire code from before the repair leftover and that one went away and hasn't come back, so I know the scanner is functioning and is interfacing properly with the vehicles electronics.
Anyways I started it up again and it again ran nice, but this time also sounded brand new with the exhaust properly fastened. But the code was still present. I drove around the ranch a bit after keeping the throttle at about 2000rpms for another 10ish minutes and it drove like normal.
Right now I'm taking a break, I disconnected the battery to see if that changes things. While the heads were off way back when, I checked to make sure I put the reg and MDS lifters in their right spots, and double checked like dozens of times before I put the heads back on, lol, so im certain they're in the right spots. Is there anywhere else in the wiring I should look? Is there a certain plug I may have missed? Any other way I could troubleshoot?
I should say a massive thank you to this forum and the active members. I was quite confident going into this repair but ran into many hurdles otw and took quite a bit longer and many more sessions than I foresaw. It's really because of this forum that I am like 99% successful so far. I really appreciate all of the support.
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