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Discussion Starter · #1 ·
Ok so I purchased my hemi 2 1/2 weeks ago, since then it has been in the shop for 1 week while they replaced all 8 of my fuel injectors since the guy before me put bad fuel in it. Luckily the warranty covered it or I would have been hella pissed. Anyway, I had dual exhaust put on and K&N 77 series CAI and then a few days ago I noticed that whenever I am going about 50 MPH and I press on the gas pedal there is very little response until I press harder and switch gears. Kind of like a dead spot, or as the mechanic at dodge referred to as a "fall out". He said there wasn't anything wrong with it though and it was a result of my aftermarket exhaust and intake and that the computer has a re-learner program that will eventually take care of it. He told me the only way to get it to stop was to drive it more and the older it gets, the smarter it gets. Has anyone else heard of this? Aftermarket performance upgrades causing a dead spot or fall out in the throttle? Thanks guys.
 

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Mine started doing the same thing after I installed my K & N intake. Been on there about a month or so, and hasn't stopped yet. May just be a flaw in the design or something. Been kinda wondering about that myself.
 

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You can reset the pcm, then let it learn from scratch with the mods.

Leave the battery connected, buckle the driver seatbelt, remove the pcm fuse (its labeled under the fuse box top), put in key and turn to start position and hold it there until you hear 2 chimes.

Replace fuse and drive it.
 

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Discussion Starter · #4 ·
Holy crap, resetting the pcm like that worked. Wow, it's like night and day. It also gave me and extra 3 MPG better. I guess because the computer was use to driving around with 8 bad fuel injectors and the mods. Thanks a lot.
 

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Ok I realize there were other problems with his, but what is the pcm and if I reset will it do harm?
 

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My hemi dead spot is because of my fat belly and short legs! Cant get the gas pedal down far enough for the hemi to kick in. But yes it gives the truck a fresh start to learn driving habits. Also I had mine RE FLASHED at the dealer during warrenty work. And that also was like driving a differant truck.
 

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mikereidjr said:
Ok I realize there were other problems with his, but what is the pcm and if I reset will it do harm?

Mike,

The PCM or "Power Control Module" is the computer that basically controlls every aspect of the truck's ability to run correctly. These Dodge PCMs have a habbit of actually "Learning" your driving habbits and adjusting specifics of how your engine runs accordingly (Mixture, shifting, timing, etc).

Whenever you do ANYTHING to your vehicle, it is a Good idea to "Reset" the PCM (Basically erase that memory) so it can relearn your driving habbits and make its' adjustments WITH the new mod added.

In this case, it seems that the PCM was attempting to learn the driving characteristics WITH bad injectors, so when he had THAT fixed, the truck PCM didnt know. When he reset it, BAM....good as new!

Resetting the PCM hurts nothing. In fact, you may notice a slight extra bit of "pep" by doing it. I reset mine monthly!
 

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Glad it worked for you.

The pcm learns your driving habits, like said above. It takes time. There are 2 fuel tables that constantly adjust depending on your driving habits and other sensor signals. One is STFT (short term fuel trim) and the other is LTFT (Long term fuel trim). Then there is timing.

If you reset it and drive it hard, then it'll learn that and adjust the trims accordingly.

When you reset it properly (disconnecting the battery will NOT do that), its like a brandy new pcm. And it will start to learn as soon as you drive it.

The reset will also delete any codes you may have.
 

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i installed the superchips to my 03 hemi...should i set it back to stock before i reset the PCM??
 

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I don't have either programmer so I really can't say for sure.

I don't know what they actually do with the pcm. Sorry I can't answer that one.
 

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Just leave the programmer in. The programmer modifies the PCM programming, but the PCM still learns and changes its responses as you drive.

Also, whenever you use the Flashpaq to change anything, the PCM is reset by the tuner.
 

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kenihemi said:
You can reset the pcm, then let it learn from scratch with the mods.

Leave the battery connected, buckle the driver seatbelt, remove the pcm fuse (its labeled under the fuse box top), put in key and turn to start position and hold it there until you hear 2 chimes.

Replace fuse and drive it.
Do you really have to buckle the drivers seatbelt?!!?
 

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key position?

kenihemi said:
You can reset the pcm, then let it learn from scratch with the mods.

Leave the battery connected, buckle the driver seatbelt, remove the pcm fuse (its labeled under the fuse box top), put in key and turn to start position and hold it there until you hear 2 chimes.

Replace fuse and drive it.
Kenihemi - when you say "turn to the start postion" do you mean where the engine is turning over or just to the run position.
 

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Buckling the seat belt allows you to hear the correct chimes and not hear all the warnings sounds from the belt not buckled.

Turn the key all the way like your starting the truck and hold it there for 2 chimes. With the fuse removed the truck will not start.

When you replace the fuse you will have to turn the key to start and hold it there as there will be a pause before the starter kicks over. It takes a second because it has been reset.
 

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Discussion Starter · #18 ·
You also have to do 2 backflips and sacrifice a dead chicken. Sacrificing a live chicken would be animal cruelty so make sure it is already dead. haha, ok kidding.
 

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What streethemi said ^^^^^.

Never tried the chicken thing, LOL!
 

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For you guys with the programmer, NO, Resetting the PCM with your Tuner settings loaded will NOT delete your program.

To be on the safe side, I ALWAYS return my truck to stock (Remove the SC program) before resetting the PCM, but it will NOT delete your program.

Resetting the PCM ONLY clears the Fuel Table memory (to my knowledge). Now it MAY possibly do some other things as well, and I guess the person to clarify this would be someone like "Dodge3471". He seems to be the "house guru" on these types of things.

if you dont want to buckle your seatbelt, what I do is:

#1. With truck Off and keys removed, Pop the hood and pull Fuse 23 (Or whatever fuse is labeled PCM)

#2. Insert keys into ignition, turn to the RUN position and wait for the normal "Chimes" to stop.

#3. Turn the key as if you were going to CRANK the truck (As stated the truck will not crank with the fuse removed) and HOLD it there and wait til you hear 2 chimes.

#4. Turn truck off, remove keys

#5. Install Fuse

You WILL notice a slight hesitation when you go to start your truck the first time after you reset the PCM. This is normal. There will be a slight hesitation from the time your key hits the "Start" position until you hear the starter actually engage the flywheel...
 
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