Low idle problem

[ebondy2]

I have a 2011 dodge Ram 1500 Laramie with a 5.7 Hemi
When I first bought this truck it would stall when comming to a stop and when going into reverse
What I've done so far.Replace head gaskets(they where leaking),cleaned thottle body,new air filter,new intake air Temp sensor, new PCV valve,New map sensor,Auto trans mission fluid and filter change,new spark plugs(old ones looked okay),This helped except when cooled it still wants to stall.When truck is warm its ok

What i have noticed is that the truck idles at 500 rpm and 600 rpm when ac is on
I bought the I3 tuner so i could adjust these up.

What i've done installed the 87 octane program with the following parameter changes idle in drive +200
idle AC on +100

Now the truck idles at when AC on at 700 rpm but still idles at 500 rpm in drive but if I tap the gas pedal and hold the brake it jumps up to 800 rpm

Any help or suggestions would great

[ebondy2]

Just an update to my idle problem
When truck is cold it idles at 800 rpm in drive(this is what i flashed to the PCM).When truck warms up and I come to a stop it idles at 800 rpm for half a second then drops to 500 RPM.If i put it in park then drive it idles at 800 RPM or slightley tap the gas pedal

My question is why is it not staying too what i flashed and also what parameter is changed in the pcm when I increase the idle speed in drive is it something I can data log

Looking for any advice

[ebondy2]

Another Update

Tried running with MDS off no change

[ebondy2]

Last Update Problem Fix

I emailed support my problem and less then a day they had me a custom tune which fixed the problem
Hats off to the support and calibration staff at Diablosport for there very quick response and help

Thanks so much

[mikel]

thanks for being patient here.

[LS1Zedder]

I am also having this exact problem with my 2017 Ram. Increased RPM +250 and everything works fine except when coming to a complete stop with AC off. Truck drops to stock 550 rpm setting. Like others putting in N, P or blipping throttle brings it back up to 800 and it will stay there until I resume driving then come to a complete stop again.

Even creeping along at less than a walking pace the idle is at 800 but as soon as I stop completely it drops to 550. Running with AC on works perfect. Always idles at 800 rpm.

I have contacted support and sent them a log file. Just heard back from them and they do not seem to have an explanation or a fix. Based on several posts here I would have thought that this was a known problem with the Hemi and a fix fairly straightforward.

I have emailed a link to this post and another like it back to the support person I spoke with. If anyone here can provide more information regarding the fix or the person they spoke with at Diablo who helped them I would appreciate it.

[mikel]

I am also having this exact problem with my 2017 Ram. Increased RPM +250 and everything works fine except when coming to a complete stop with AC off. Truck drops to stock 550 rpm setting. Like others putting in N, P or blipping throttle brings it back up to 800 and it will stay there until I resume driving then come to a complete stop again.

Even creeping along at less than a walking pace the idle is at 800 but as soon as I stop completely it drops to 550. Running with AC on works perfect. Always idles at 800 rpm.

I have contacted support and sent them a log file. Just heard back from them and they do not seem to have an explanation or a fix. Based on several posts here I would have thought that this was a known problem with the Hemi and a fix fairly straightforward.

I have emailed a link to this post and another like it back to the support person I spoke with. If anyone here can provide more information regarding the fix or the person they spoke with at Diablo who helped them I would appreciate it.

A fix was identified and you should hard from our team shortly with an update.

[LS1Zedder]

That is great news. Thanks very much for you help.

[LS1Zedder]

Update

Customer support has been great and I have been working with them for a couple weeks now. A big thanks to Rick Courte for working with me to try to find a solution. They have sent me two custom tunes which I have tried but unfortunately without success. The truck still does the thing where with the AC off coming to a complete stop drops the idle down to the factory 500 requiring a shift to P or N then back to D or a blip in the gas pedal to bring it back up to the new setting. AC on works fine.

At this point the Engineers don't know what else to try. Going forward I can work around this problem but if there is a chance that it can be resolved as in the original thread poster's case that would be ideal. I have reached out to him with a PM but have not heard back. He shows as not being active since 2019 so I don't believe I will.

Is there anyone else who has had this problem with a ram or a 09-17 Hemi who can shed any light on a possible solution? I would greatly appreciate it.

FYI my Ram has the 6 speed, column shifted transmission. I am also using the T2 tuner. I know this is an i3 forum but I wanted to tag onto this thread since I am having the same issue.

Thank you

[mikel]

just to be clear, it will do this with the stock tune as well?

[LS1Zedder]

just to be clear, it will do this with the stock tune as well?

The stock, unmodified tune idles at 500 rpm in Drive, Park and Neutral in with the AC on and off.

Modifying the stock tune with +250 rpm across the board results in the conditions I have described above. Everything works great except for coming to a complete stop with the AC off. Bliping the throttle slightly or shifting to N and then back to D keeps the idle at the new setting until driving then coming to a complete stop again. This is the case with the Modified stock tune, 87 Octane tune and both the custom tunes I have tried.

[LS1Zedder]

I have discovered one other scenario where the new programmed idle works with the AC off. As I was sitting at a stoplight yesterday the AC was off and idle had dropped to the stock 500 rpm. While I was stopped the electric radiator fan turned on the idle immediately jumped up to the programed 850. I tried again as a test, stopped completely and the rpm fell to 500 and I waited while the temperature rose. When the rad fan turned on the idle jumped up once again.

So there are now 3 scenarios where the truck will resume the new idle setting while stopped with the AC off.
1) Shifting to N or P and then back to drive.
2) tapping the gas pedal while stopped
3) Radiator fan turning on.

[mikel]

very strange. load the tune with the idle adjusted and then post the backup ad last tune written files from the tunes folder here please.

[LS1Zedder]

PCM_68298482AF_LastTuneWritten.drg

PCM_68298482AF_Backup.drg

Here they are. I have the modified stock tune loaded with idle +250, 10% throttle boost, Fan temps lowered to 196.8 Deg and MDS turned off.

Thank you