Hey everybody. I have a 98 Durango 5.2 that i bought about a week ago. It has started backfiring pretty bad at about 20-30 mph when i am accelerating. The CEL came on and it was an 02 sensor. Would the cat be causing the backfire and the CEL? If so is it worth getting a high flow cat and where can i get one from? Thanks

 

the o2 sensor could be making it run realy rich, and that would cause it to back fire. a high flow cat would add so power and you can find them at summit or jegs.

 

I would change out the o2 sensor, and go from there. Do you get a smell like rotten eggs in or around the vehicle? If not then chances are that the convertor is not plugged up. Try the sensor first and go from there.

 

If it was a dealer i'd tell ya to bring it back and get er fixed. But for now, i recomend a tune up (Spark plugs/wires/cap (brass) rotor/oil etc). Theres no need for a high flow cat other than it being louder no gains, OEM cats are best ran on our D's and the flow is sufficient enough, anything else is just useless (unless cheaper). If you chose (never hurts and can actually help mpg-slightly) to replace your o2 sensor i would recomend doing both, make sure you get plug and play sensors and not the cheap azz universal where you have to splice the wires.

Edit** Since its a new purchase, have you had it on the road for awhile/ refueled etc ? Just a question to see if maybe theres a lil water/old gas in the tank from sitting before purchase.

 

Yeah i put in a full tank of gas just after i bought it. I am going to get the 02 sensors from autozone so i dont think they are the universal ones. I will change the sensors and do a tune up on it the end of this week and see if it helps

 

I would double check the part before you leave, a lot of autozone parts are universal and not plug and play.

 

I would replace the 02 before you cause harm to the CAT. Just get it ASAP! After the replacement, I would take it to a muffler shop and have a back pressure test ran on it just to make sure it is not plugged. There should be no more that about 2 1/2 lbs. back pressure. Any more than I would replace it.

Most shops will do this for you for free. If you do need to change it out then I wouldupgrade toa 3" high flow. This way when you plug in with a cat back system maybe later in life it is already done for you. Hell, ya gotta pay for it anyway you might as well get something you like.

 

I am getting the 02 sensors changed out Friday. But for now i am doing a tune up. What should the spark plug gap be? And does anybody have a diagram or something for the spark plug wires because i crossed one side of them up. Thanks