Idle/take off misfire

[all n.a.]

idle issues, no codes, would like some help

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The situation is one night I had the car ready to make a few runs. Put 5 gallons of 110 leaded in the car mixed with 91 rest of the tank. Car ran like a champ till it got down to about half a tank. I was unloading it off the trailer and had to get out to check clearance, while i got out to look all the sudden i noticed a big change in tone on the idle and it was idling very rough. The next day i took the car out and only when i would hit stop lights the car would load up sputter and run like garbage so bad i couldnt harldy drive it, eventually it would clean up and run fine.

Now since then i figured the leaded just killed the o2's. Its had new o2's put in, been through 4 tanks of gas, new fuel filter, has 58psi fuel pressure at the rail. Checked the primaries with a heat gun and are within 10 degrees of each other. The car now doesnt load up so bad, however at every stop light and slow accel to pull away it sputters and runs like crap until i hit about 2300 rpm then it clears up and runs fine.

I do have hptuners and am not very knowledgeable using it yet but have friends that are. We did some messing around with the car making a few adjustments with fuel in the main VE table that needed changed reset the fuel trims so as they would reset now that the o2's are fresh. Nothing is working and its very frustrating that it has this driveability issue. When we turned off closed loop at idle the car ran perfect every time from stops and slight accel. I've noticed that during a log the o2's are all over the place at idle on the lean side and set for tune around 14.7afr during normal driving and idle. The o2's sit in the upper 15's sometimes low 16s for afr and dont cross the 14.7 for almost 16 seconds or better. However during normal driving, the o2's are perfect and following each other exactly. Sorry for the long post but if any of you have an idea what i should look into i would appreciate it.

The first log is just a idle only log and the second one is a idle and light driving log

The motor is a lq4 with a 231/235 .617/.621 110+1 LSA cam

[SargeZ06]

Did you check the plugs? Turn the O2s off and see how it runs. Reset your fuel trims too.

[miller456]

thanks for the reply sarge, this is my car thats having the issue. Ive been through two sets of plugs. Both of which looked fine, and timing marks were good. Fuel trims have been reset already after new o2's were put in. I turned closed loop off at idle and the issue went away. Not sure if this helps pin point the problem?

[miller456]

anyone else have some thoughts? I also notice when i first start the car on cold temp. and drive it, there is no sputter. Once the car is up to operating temp, then the issue starts.