Something that has bothered me for a while, my a/f is fine WOT and PT but just cruising around but sometimes (after the engine/trans is fully warmed) the a/f pegs out lean 17/1 at steady throttle in tc lock. If I blip the throttle it will return to normal but soon go way lean again. After a while it'll run 13's rich and then stoich again. All this at steady cruising throttle.
I replaced the wideband O2 with same results. This started happening immediately after going to the true duals.

Thoughts? I dont have any scanning software (someday) and it never does it on a short ride with my tuner scanning, lol. He says it's not a concern, that it's just the 'trims' but it does feel differesnt (and it sounds different?) when it goes lean like that.

 

Thinking....... ummmm yeah that is strange. My first thought was o2's but apparently so was yours. It does sound like trims but its trimming for a fueling problem and to slow it sounds. Has to be tune related and I personally would be concerned cruising at 17/1 AFR for any extended amount of time.

 

Mine does the exact same thing. Haven't addressed the issue with Allen Nelson yet but will on Friday.

 

I am concerned but my tuner says it's not an issue. As soon as I apply any throttle it goes where it should. Could a very small exaust leak in front of the O2 cause it to do that but not be heard?

Really, keep me posted if you find a cause!

 

I only replaced the WB o2 which of course is only reading - not affecting. If a forward o2 was weak or burnt would it throw any codes?

 

Yes a small exhaust leak could cause this IMO and yes a weak/slow o2 could also, especially if it doesn't stay heated to similar temps via the exhaust flow, and not throw codes again IMO.

 

Just found this thread, mine does the same! What bothers me is when I am climbimg a hill I'll see 17:1 under a pretty good load. I have to get into PE/boost to make it change. My gauge sweeps back and forth between 14 and 17. Strange!

 

I talked to Rick some more about it today and agian he really doesnt think its anything to be concerned with but we'll take a ride soon and see if I can captute it while he's plugged in.
Henry, mine comes back down as soon as I give it any peddle. You have tuning software, have you scanned the event?

 

Maybe your O2's are a little dirty, you might try cleaning them? I mean you are throwing a ton of gas, meth and nitrious into the motor. I may be way off, but worth a shot

 

No, I have only experienced it cruising on the hwy. I am also not smart enough yet to get scans that show me more than the digital dashboard in EFI live . I'll look around for a tutorial or something, I need to put my software to better use!