Installed trans temp and air/fuel gauges the other day and I've noticed that the truck seems to run on the rich side while idling and driving normal. The computer seems to be working on keeping it at 14.7 but its jumping between rich and lean constantly. If I floor it it will stay pegged rich but as I understand this is because the computer sees full throttle and increases fuel. Is this normal or something else? I was thinking of changing the plugs since they've been in there for awhile and upgrade the wires. Mods are 2.5" exhaust after the factory Y with a magnaflow muffler turned down, Volant cai w/ box, and nothing else done performance/wise. Plugs are the stock ac delco's. Was thinking of going with some ngk tr5's. I'm used to dealing with my muscle cars and carburated engines but getting the bug to upgrade my "work truck".

 

The jumping between rich and lean is totally normal when under light load. Going rich at full throttle is also normal.

The stock wires are hard to improve upon. You won't see any performance gains from swapping them out .

 

If you are running the stock narrow band O2's then at WOT it should light up the last 2 greens, which is about 12.2A/F. 14.7 is in the dead center, and 13.5 is about where is starts going yellow.

The jumping back and forth is the computer constantly adjusting fuel to keep it stoich.(14.7) Thats a good thing.

 

Ok, thats what I kinda figured. Thanks for the replies.