i have an 04 caravan with a 3.3 v6. i have had a P0406 code for a few months.. no MIL or running problems.. until today i noticed a slight skip when barely accelerating. i have 88 k miles on it, so i changed the plugs and the wires... now i have a knocking and pinging noise at slow acceleration when alreay driving.. i do not notice it when accelerating from a dead stop. so i pulled all the plugs and checked the gaps (autozone says you do not have to do it) and 4 of them were .10 off.. so i regapped and tried it again.. no change other than i have a little better response when trying to accelerate... i am confused. i do not know what the code is and do not know why i have a noise after changing the plugs and wires.. any help would certianly be appreciated

 

P406 is a EGR code, if you had a P0306 you would have a misfire code. EGR will also cause a knocking/ pinging sound.

 

i should have remerbered that i also got a half tank of gas when i came back from getting the parts... haaa.. got more gas today and the noise stopped within a couple of mins...bad gas what a nightmare.. anyways i still have the P0406 code and sometimes it seems to have a hesitation when accelerating from a dead stop.. maybe it is part of the egr system prob.??
any info on what to check or how to check so i can locate the problem??
Thanks !!!

 

Very common problem. The position sensor inside the valve goes bad. Have to replace the whole EGR valve. Puts out a variety of codes from P0401 to P0406. New valve solves the problem. Easy to replace

 

I will get one and let you know how it goes!!!
Thank you !!!
John