i posted a while back about a funny idle when starting my truck after the engine is warm. it is still doing this occasionally but now when it does it if im in reverse then go to drive it stalls. any ideas on what this is? also i just did my cat and now my downstream o2 is going, gave a code p0139. is this a common issue when the cat is replaced? by the way its an 03 dakota qc slt 4.7L 4X4. thanks

 

you change your sparkplugs at all?

 

i changed them about 10k ago. put in platinums

 

take those out, for some reason, mopar engines cant stand platnium plugs... throw in the regular oem replacement plugs, i run ngk in my truck and im fine, others have autolites or you can go back to champions if you please, bosch plugs, stay away from IMO