I have a 98 Dodge Ram 1500 Quad Cab which I bought in February of this year that has been sitting up for a while...

Parts/Services I have replaced/done.
Plugs and Wires
Oil Change
PCV Value
Air Filter
Radiator Flush
Map Sensor
Idle Air Control Sensor
Throttle Positioning Sensor
Distributor Cap
Rotor Button
Battery
Catalytic Converter
Duel Exhaust Pipes
Cleaned Throttle body

Issue #1.
When you first start the truck the engine is very loud when you take off and will not come out of second gear for about a half mile...
After that it quiets down and has no further issues while on this trip
however once you turn it off and restart it you will have the same issue...

Issue #2.
When truck is idling the is a vacuum sound that comes from the throttle body and the truck wants to die... This is a random sound/issue and is not continuous... The Dodge Dealership told me it was back pressure from the Catalytic Converter being stopped up so I replaced everything from the Catalytic Converter back... I still have the same issue... The sound also is made when I take off or when giving the truck extra gas...

Please advise if anyone has any solution to fix my issued...
Additionally when I purchase this truck I was getting 10 miles per gallon.
I currently am getting 11.9 miles to the gallon.
I am thinking that this is due to my current issues...

Thanks in Advance...
Tim...

Updates/Responses
Reply to dodge dude94:
#1. I havent had the trans fluid and filter changed yet...
Please explain TB...
#2. The IAC I got from AutoZone. The brand is Duralast Link... I have put two new IAC sensors in just to check to be sure it wasn't the sensor...
The vacuum sound is not continuous just random while idling or taking off...

Reply to thompson1986:
My Check Engine light did come on randomly before I replaced the Catalytic Converter and exhaust. When I had it checked at AutoZone It did say that I needed to replace the O2 Sensor before the Catalytic Converter. However the Check Engine light when off after I replaced the Catalytic Converter and exhaust and hasn't come back on since...

 

#1
I don't see a trans. oil and filter change on that there list.
I would try that to see what happens. Also check your T.V. cable. It's one of those cables on the passenger side of your TB, I don't know which one. Someone will tell ya that.

#2
Check your IAC again.
Where did you buy it? What brand?
Our trucks have a bad habit of not liking certain brands and whatnot. It's also not uncommon to get a bad one.

Welcome to DF!
Happy wrenchin'!

 

issue #2 i have, i thought catalytic converter but turned out to be a O2 sensor being off value, it throws a code for me though and im replacing it within the next two days, PM me so i dont forget this thread and ill tell you if it fixed it or not as i have the exact same issue

 

this might sound odd but i had kinda the same problem... on your transmission on the drivers side there is a sensor its good size unplug the wires and remove it ...on the end of it is a magnet and if it is broke or chipped it will cause the truck to have issues staying running its like 25 bucks at O'rileys i hope this info might help..........mine didnt throw a code when this happened either. but its something to check out

 

I had the same shifting issue, to get it to shift outa second i had to get up to speed let it coast and shift. I solved this by doing a filter and fluid CHANGE not a flush, and having both bands adjusted. But mine also had alot of brass shavings on the magnet so all you can do is pull the pan.