5.0 throwing codes!?

[foolio]

On my 96 2wd 5.0 it always had light on from bad o2 sensor but always ran great. All of a sudden the other day it started to run rough at idle and also sounds like a lttle back fire if I give it a rev. I changed the o2 but its running rough still with a code of 401 and 306. An egr system problem and missfire on cyl 6. Where do I start besides throwing money at it with out knowing the cause. Thanks in advancef

 

[bobflood]

On my 96 2wd 5.0 it always had light on from bad o2 sensor but always ran great. All of a sudden the other day it started to run rough at idle and also sounds like a lttle back fire if I give it a rev. I changed the o2 but its running rough still with a code of 401 and 306. An egr system problem and missfire on cyl 6. Where do I start besides throwing money at it with out knowing the cause. Thanks in advancef

Start with the two codes. Cylinder #6 misfire could be coil, plug wire or plug; have to do more testing to determine specifics. Same with EGR system - could be the EGR valve, or some other part of the EGR system. Again, more testing/analysis is required. Good luck.

 

[foolio]

i just did plugs and wires 2 months ago.

 

[drbenz]

Try pulling #6 plug to take a look, see if it is dry or wet with fuel and check to make sure that the wire didn't rub against something and short out.

 

[foolio]

is it possible for exhaust leak to cause problem? it sounds like my exhaust leak got a lot worse at the same time the other problems occured, i finally got under it and it seems like the exhaust leak is from the top of the front right catalytic converter