well i have a 02 ram 1500 5.9 and when i start it it idles rough for what may be about 30 seconds to 1 minute and then smoothes out and runs smooth the rest of the trip if it set for a couple hours will do the same thing but not as long as the first start of the day seems like it is running rich see a little black smoke untill it clears up i have a check engine light but i dont have a scanner to read codes right now any help would be appreciated also i guess i should add it has 230,000 miles might help

 

That could be many issues

Personal experience - maybe a fuel injector, o2, cat - Seems like the component needs to "warm up". Honestly I could list another 30 components. You need to get that code from the CEL. Go to autozone and have it pulled. Then we go from there.

I know that you can get the codes from turning the key on and off 3 times for my 05. I cant say the same for your 02. PLease search for pulling the CEL code and see if it can be done without a scanner.

 

Stop by your local auto parts store - about all of them read codes for free now. Impossible to diagnose without seeing the truck if you don't have the code...

 

alright guys i read the codes and it said multiple cylinder misfire and cyl 3 and cyl 5 misfire and that is all so i pulled all the plugs and wires cap and rotor did compression passenger side bank all within 10 pounds of 180 on the drivers side bank 1 was 190 3 was 180 5 was 180 and 7 150 all the plugs looked decent but worn gap really large they have about 100k on them but no oil or any buildup 5 had a rust color on the insulator so i dont want to pull it down right now to possibly do the valves sounds to me like they are a little weak on that bank so i put new double platinum plugs autolite prfessional wires and new cap and rotor and airfilter checked fuel pressure and it is steady at 48psi from my research that should be right on and when off no bleed off on the pressure settles at about 40 psi and stays there so now im going to see how it does in the morning when i cold start and see if the miss and rough idle are gone i believe so i scanned it and all the o2 sensors are working good tps is right on everything read good so hopefully it will fix it thanks for all your help

 

I have an 05 3.7ltr, had an 04 3.7 Dak, at 30k on the Dak, the stock NGK plugs were burnt, Not that there bad plugs but long highway trips do tend to kill spark plugs in these engines, not sure about your daily habbits, but mine is 90 minutes highway 5 days a week. I switched to double platinum plugs (bosch) and that seemed to take care of my problem.

 

double platinum plugs and autolite wires are going to disappoint you.. ping city..

check your plenum gasket for failure.. sounds like you may be hearing some pinging which is indicative of blown plenum, along with the misses... if your plenum is blown, you're likely to have a clogged cat as well..