Rpms drop when coming to a stop

[BigBlue05]

Whenever I first start up my truck wether the engine is hot or cold and I come to a stop the rmps drop. It only does it once after I start it up. But it doesn't always do it in only occasionally. But within 1-2 seconds they go back up. Also don't know if this is related or not but when I'm cruising at highway speeds usually anything over 60mph and I go to accelerate if I push the pedal down it take a good 3-4 seconds to get a response. But if I push it down to anything over about 75% throttle it responds instantly. Like in said not sure if related but figured I give as much info as possible. Also the egr valve was replaced about 2 weeks ago.

 

[ramportin1]

i believe 05 does have MDS right? i know on my 07 it would do that drop RPM's at a stop for a second then it would actually shoot itself back up, if you werent on the brake it would be enough to push the truck forward. also randomly at med throttle it would for a split second BRAAAAP then back to med throttle, was embarrising at times because i had exhaust so it would happen and people would think i was trying to show off or something lol. anyways having the MDS disabled from a custom tune solved both those issues. its been like 2 years or so since i got my trinity and hemifever tune and never done it since, yours sounds real similar to what mine did

 

[chrisp2493]

05 doesn’t have MDS, it started with 06. I think it being laggy on the highway has more to do with the stock tune. Getting a tune, especially a trans tune will help it be more responsive

 

[MADDOG]

What RPM does it drop to?

 

[Ram-Rod]

Have you looked into anything? Could be a nasty throttle body/IAC stuff. Check that out!

 

[ramportin1]

05 doesn’t have MDS, it started with 06.

Whoops lol

 

[chrisbh17]

Have you looked into anything? Could be a nasty throttle body/IAC stuff. Check that out!

This.

My old 5 speed Beretta would do this, it was the IACV needing re-learning, but I imagine if its all gunked up it would respond similarly: as you get off the throttle and the engine attempts to idle, it drops too low before the IACV can respond.

Check the throttle butterfly too, for the same reason: it wont respond as quickly as it should if its all gunked up.

 

[BigBlue05]

The rpms drop from 700 to 300-400. And yes the throttle body was recently cleaned. Also replaced the iat because I broke it taking off my intake.

 

[WilliamS]

Im going to 3rd Idle air control valve. Its not a hard fix but it will make the whole truck smoother.

 

[BigBlue05]

From what I have read the iac valve isn't serviceable on my truck

Is it possible im looking at a fuel problem?

 

[BigBlue05]

Found the problem and fixed it. It turned out to be my map sensor.

 

[Lowwhiteram02]

My 2017 ram 5.7 drops idle from around 800-1000 to right above 500

 

[BigBlue05]

My 2017 ram 5.7 drops idle from around 800-1000 to right above 500

Don't really know about 2017 hemi but could that be from it dropping from 8 cylinders to 4?