I have a 1997 dodge ram 2500 4x4 360 that runs fine when cold after it warms up it gets a loud sucking sound then dies. Start it back up runs fine fo a couple mins then does it again .no trouble codes. We had a cold snap here in ohio for several days and it ran fine and now that it warmimg up it does this runs fine as long as its on the floor but misses and pops through throttle body when trying to maintain a stedy speed
Any ideas

 

the loud sucking sound is most likely the IAC motor (stuck open i believe, could be wrong), or it could be a intake plenum leak or a large vac leak elsewhere. there are ways to track down the leak by using a propane torch (dont light it), or you can use carb cleaner. you can also remove the IAC motor and try cleaning it w/carb cleaner, i would probaly get a new IAC gasket when replacing the cleaned IAC motor.. oh, it could also be leaking between the air box and throttle body there is a gasket there that goes bad, or in my case you buy the truck and notice that the previous owner either lost the gasket or didnt put it back on after he relaced the air filter. that leak (sucking sound) was not hard to track down.. speaking of the TB, that gasket might be shot as well along with the body needing a good cleaning restricting the IAC due to build up..

as far as the missing, when was the last time it had a tune up (plugs, wires, ect..) ever try running sea foam thru the gas tank to clean out the fuel system? i do it once every 3 months and it does help after awhile as far as MPG and such.

where you at in ohio bud? im in the cleveland area.

 

Unplug front O2 sensor, see if it runs any better.

 

I am in the gallipolis area
The weird thing about the sucking sound is it only does it after it warms up on on a realy warm day
I can shut it off after i start hearing it and when i start it back up it takes a few mins for it to do it again

 

honestly not sure where that is.. your symptoms are exactly one problem i had w/for about a week(loud sucking and poor idle). i replaced things one at a time and my cure was the new IAC motor. that did not take care of my rough idle problems after it warms up, but i pulled my pre-cat o2 and saw how nasty it was. so i went and got a new NTK o2. see if that cures my rough idle as i have a new TPS, IAC, super clean throttle body now and new gasket for it. my plugs and wires dont look to bad from what i can tell, so figured i'd try the pre-cat o2 before i go any further.


and just a FYI, NTK o2's from advance are like $70.99 so if you can wait for shipping i would order the sensor from rockauto.com as it was under or around $40 iirc. and if you do order it from rockauto (if you decide to replace it) let me know and ill send you the 5% discount code for them.

 

just figured i would update since ive had drive time w/my new NTK now. ran around all morning/afternoon, w/many startings and idle time and not once did i get a rough idle. and at one time i let it sit and idle for about 10 mins and it stayed steady. seems to be that was my rough idle issue, along with the filthy throttle body and bad IAC motor.

i will keep monitoring it for the next few days tho.

 

almost positive mine is the iac also let ya know when i get a new one

 

ok at my witts end
removed throttle body and cleaned, replaced gskt, new iac, new air cleaner gskt still have same problem runs great till it warms up uuuuugh then at idle the loud sucking starts again and the noise i def coming from where the iac is

 

Unplug front O2 sensor, and try it that way for a couple days. See what happens. (CEL will come on though.)

 

I am attempting to yell this, as this is the second time HeyYou posted it.

The problem is NOT the IAC. as the IAC is only an issue at idle. The problem is more likely a blown plenum and maybe some other issues as well, related to the plenum.

This is why HeyYou mentioned to pull the O2 sensor. He is trying to get information to help you diagnose the problem.