Engine losses power in hot days

Xzena3

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I have a 2014 Ram 2500 5.7L with 4.10 gears and 150k miles. At the beginning of last summer I started getting a loss of engine power after sitting in heavy traffic for an hour or more with ambient temperature at or above 90 degrees. The condition doesn't feel like a dead miss but rather like the engine is de rated. When I hit the throttle and hold it at let's say 1/4 there is a noticeable lack of power. If I stay on it after a few seconds it comes to life and feels normal. I have tried manually shifting and there is no change. Once the condition comes in it will stay that way for several days of driving with no traffic before it clears up. I have disconnected the battery and it seems to make a big difference but the next time I am stuck in traffic it returns again. I replaced the plugs at 100k and perform all required maintenance. There are no codes and it does not happen in cold weather (no issues in the NE winter). I was thinking maybe a weak coil pack but I don't have any misfire codes to support that. Any ideas on what to check?
Thanks in advance
 

bluebeast1562

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Sorry mate, cannot help you. Should post to the 4th Gen section to see if anyone else in the generation has had the issue.
 

ramffml

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You running 87 or 89 octane? I thought more than once I felt a similar thing, but generally when I'm hitting 2000+ rpms (climbing a hill or passing someone) and much more noticable on hot, humid days with 87. Never noticed it in winter either. I switched back to 89/91 for towing and I swear my truck runs better but I hate to put too much weight on what I think I feel.

All I can say is, if you're running 87 try bumping up the octane.
 
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Xzena3

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Thanks. I do run 87, I never noticed enough of an improvement when it is running right to justify the cost but I will give it a try.
 

ramffml

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Thanks. I do run 87, I never noticed enough of an improvement when it is running right to justify the cost but I will give it a try.

As costly as it might seem for a test, I'd fill up at least twice with 91 (if you can afford it) before forming an opinion on whether it's helping, just because you have left over fuel in the tank that's 87 so mixing (for example) 89 with a quarter tank of 87 is still going to drag you down to 87-88. If you put in 91 then it will down mix to 89ish for the first tank etc.

Technically we should see no difference with 89 vs 91, but again that's in a perfect world with no 87 in the mix/tank or in the hose from the previous guy etc.

I plan to throw a bottle of seafoam in my next tank as well.
 

Hookedup87

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I believe our Hemi engines suffer a lot from heat soak, and from what I understand, the computer begins pulling timing out under those conditions which would definitely result in a feeling of lost power. These engines are programmed to run very hot for both emissions and fuel economy purposes.
 

Burla

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My trucks runs like a dog with 87 and runs like a rap-ed ape with 91.

Anyhow, more molecules = more energy and cold air has more o2. Cold air is denser so it has more o2, not as a % as in you get more other molecules as well, but more o2. You can try a cai as well.
 

seabrook

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My trucks runs like a dog with 87 and runs like a rap-ed ape with 91.

Anyhow, more molecules = more energy and cold air has more o2. Cold air is denser so it has more o2, not as a % as in you get more other molecules as well, but more o2. You can try a cai as well.
yep mine too but i pay very close attention to how my truck runs
 

Dirty D

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100% i almost never put 87 in my truck, even before i got it tuned and some mods. i do notice a massive diff in quality depending on where i get it from as well. if i hit up the sonoco pump and grab their 91 vs Shells 91 lol world of difference there as well.
 
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