01MGGT

So got the car running pretty good with a stable idle now with the cams but according to the recon software the left bank is running leaner than the right bank. I have no CEL on at all. No exhaust leak that I can hear on that side either. I have attached the log file from recon. If you guys don't care please have a look and give some input on how to go about this...thanks!
http://www.mediafire.com/file/myjgy3g2ntt/warmidle.xml

01MGGT

Wow no replies huh. I am just going to pick up a. O2 sensor today to eliminate that. Do I do anything special to reninstall it like a free air calibration or anything? Also do u maybe think the stock fuel pump can't flow enough fuel to fed the larger injectors maybe? Once I get this sorted out I should be good!

cliffyk

I just looked at and replayed your log--there's nothing wrong that I can see, the left and right fuel trims (short and long) will never be simultaneously the same as they are separately controlled by the PCM--that's why there are two O2 sensors.

They are both within +/- 6%, except for a 2-3 second period around 10:40:30 to 10:40:33 where bank 2 went up to 7%-9% for a bit--however with cams at idle this in not unusual.

The long term on bank 2 is high at 16% to 17%, however you should disconnect the battery fdor 5-7 minutes to reset the KAM and see how it comes back in--but unless you can really drive the car around a bit (at least 50 miles at cruising speeds) don't let the LT trims freak you out as long as they are within +/- 20%.

01MGGT

Awesome cliffy. I knew I could coun't on you. I have always heard the left bank on the 4.6 runs leaner anyways. I pretty much can't drive the car that far right now as there is like 2 inches of ice on most the roads. Some of the points in that log I was turning the accessories on and off to test the stability of the idle speed and the car not dying. The guy helping me with the tune was sayign the bank was way off and I guess that got me a little worried.

cliffyk

It (bank 2) is running a bit leaner than bank 1, however it's not running lean--it's just requiring a bit more positive short term trim to get it to 14.68:1.

As long as the STFTs are within +-15% at idle your cool. The cams will mess with AFR at idle as the extended overlap allows more unburned air/fuel to be sucked through into the exhaust. The unburned mix is both cold and has a high oxygen content--I.e. the PCM thinks it's lean and adds fuel vis the STFT.

Greg Banish says in his book "Depending on the amount of overlap in a camshaft, it may be necessary to ignore HEGO outputs at low load or even altogether for fuel trimming purposes."

I have never seen the "ignore..altogether" situation, however fuel trims at idle are largely irrelevant for a cammed engine--unless of course peak HP at idle is one of your goals. At higher loads and speeds this issue goes away.

01MGGT

Thanks ciffy That explanation puts me at ease and I will hold off on even doing anything to it

Imfamouz_Duche

may i ask how you like the sniper software i have been looking in to it

ChalknCover

There really is nothing like it that gives the user that much info and control. I highly recommend it.

Imfamouz_Duche

May i ask where you got it from it says 600$ on their website but o did you see actual gains?? mpg or power

01MGGT

I have been very happy with it so far. If I didn't have it I wouldn't have the car up and running yet! There are some bugs in it but they are being patched I heard. The community support for it is awesome too. I haven't been able to really drive after the tune yet bc I am in Alaska. But I can tell a huge difference just in how the motor sounds. Cliffy can probably answer any question you could possibly have. My only worry is finding a dyno tuner that uses sniper when I get back to the lower 48. Really don't want to have to buy a hand held tuner when I go boosted. It also comes with free data logging software too.