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I haven't driven the truck the last 3.5 weeks and the last time I drove it I towed the 5th wheel 190 miles home with some fuel injector cleaner in the tank and parked it. This last Monday I drove the truck to work and noticed a very light hesitation in 2nd gear and low rpms, very very light and it was intermittent. I topped off with fuel wondering if the 4 week old fuel was an issue, despite having a little injector fuel left (took 28.1 gallons). I topped off with 91 octane (towing this next week and Costco doesn't have mid-grade). The hesitation came and went, never strong. Then it dawned on me that i replaced the battery Sunday so maybe I set some codes without a CEL and it would run better if I cleared them... sure enough a whole host of low voltage codes and and active P1521. They all cleared.
So backstory... I've had the p1521 both active and pending intermittently since I bought the truck in April. I thought it was related to high oil temps, but it doesn't appear to be. I can't find much info on this code. I'm running PUP 0w-40 and a Wix 57060. The current oil has 800 miles on it.
I have been getting great mileage this week, almost 14 mpg according the the EVIC, and MDS is engaging more often.... similar results to when I ran the same fuel injector cleaner right after buying the truck.
The hesitation seemed to be better after clearing the codes, but yesterday on the way home I felt it again accelerating from a stop sign so for fun I smoothly went WOT and felt it misfire multiple times followed by a flashing CEL. I backed off the throttle and it was running really rough, so I pulled over scanned it and cleared the codes. P1521 and P0308 were both pending, not active.
Clearing the pending codes and restarting the truck it went back to running smooth. Another high rpm accleration got me the misfire and flashing CEL again, but it didn't run rough when I backed out. The misfire doesn't happen until rpms are higher, maybe 4K and up.
So that's where I am at today. I am thinking of swapping the #8 coil pack with another cylinder but also can't overlook the coincidence of just running injector cleaner and changing the battery. Anyway those are related? Could the cleaner have broken some deposits/debris loose and partially plugged the #8 fuel injector? With the P0308 only pending and not being fully set I don't feel like it's a big or hard failure.
Despite the higher miles, 156.8K, I don't have any Hemi tick. It generally runs very quiet and super smooth. I do have what sounds like a light exhaust leak on the passenger side, likely a manifold as the PO replaced the manifold gasket just before I purchased it and the leak is still there. The leak goes all but away when HOT, like towing, and get's 2-3 times louder in MDS.
Thoughts? Not much on Hemi's with a P1521 or misfire codes.
So backstory... I've had the p1521 both active and pending intermittently since I bought the truck in April. I thought it was related to high oil temps, but it doesn't appear to be. I can't find much info on this code. I'm running PUP 0w-40 and a Wix 57060. The current oil has 800 miles on it.
I have been getting great mileage this week, almost 14 mpg according the the EVIC, and MDS is engaging more often.... similar results to when I ran the same fuel injector cleaner right after buying the truck.
The hesitation seemed to be better after clearing the codes, but yesterday on the way home I felt it again accelerating from a stop sign so for fun I smoothly went WOT and felt it misfire multiple times followed by a flashing CEL. I backed off the throttle and it was running really rough, so I pulled over scanned it and cleared the codes. P1521 and P0308 were both pending, not active.
Clearing the pending codes and restarting the truck it went back to running smooth. Another high rpm accleration got me the misfire and flashing CEL again, but it didn't run rough when I backed out. The misfire doesn't happen until rpms are higher, maybe 4K and up.
So that's where I am at today. I am thinking of swapping the #8 coil pack with another cylinder but also can't overlook the coincidence of just running injector cleaner and changing the battery. Anyway those are related? Could the cleaner have broken some deposits/debris loose and partially plugged the #8 fuel injector? With the P0308 only pending and not being fully set I don't feel like it's a big or hard failure.
Despite the higher miles, 156.8K, I don't have any Hemi tick. It generally runs very quiet and super smooth. I do have what sounds like a light exhaust leak on the passenger side, likely a manifold as the PO replaced the manifold gasket just before I purchased it and the leak is still there. The leak goes all but away when HOT, like towing, and get's 2-3 times louder in MDS.
Thoughts? Not much on Hemi's with a P1521 or misfire codes.
