LTFT's uneven at idle

[ArKay99]

My driver's side LTFT is -3.9% at idle (cell 19), and passenger's side LTFT is +10% to 15% at idle (cell 19). I am also getting a flashing Check Engine light. And the car is running pig rich. The HOS's are averaging very close to even, (within a few millivolts) The Injector Pulse Rate is higher on the passenger's side. I checked all intake paths including the manifold with propane and by eye, swapped injectors side to side, checked AIR and changed AIR check valves, put new front O2 sensors in (old ones were acting up), and checked exhaust (Kooks headers - no visual or audible signs of a leak), AIR fittings, collector fittings, and found a small leak in the midsection that I repaired (O2 WB bung had a faulty weld - my bad). I still have the same problem. I also had bad wires and fouled plugs at one point but changed those. No burnt wires, etc. Tonight I am swapping coil packs. I am also getting the scope out and will check the coil pack connector at the coil side. If that doesn't work I am putting on a borrowed LS6 intake manifold, I have a ported FAST 90 and am wondering about an internal leak (but doubtful).
If I have a misfire would it show as a lean bank or a rich bank? I'm thinking lean with higher IPW and similar NBO2 readings. WBO2 reads ~14.6.
What am I missing?

[TAQuickness]

flashing cel is indictive of a missfire. If you are misfiring, then I would expect you to be rich, not lean (as indicated by the positive trims). What codes are you throwing?

[johnsZ06]

A friend had a similar problem. He later found his O2 sensors were swapped left to right. Car ran like crap and threw codes.

[ArKay99]

flashing cel is indictive of a missfire. If you are misfiring, then I would expect you to be rich, not lean (as indicated by the positive trims). What codes are you throwing?

The car has a AFR 205's milled .030" Cometic .040", a 224/228 .581"/.588" 112LSA at 112 ICL, Comp 850 lifters, all the bolt-ons, and a LSX90/NW90, along with Jesel SS's and some other goodies,(LS6 PCV, etc.). Also, I put a 2002 Z06 operating system in to get the OS updates and edited all the tables I changed in the old operating system. I was getting a P0300 but I turned that off until I could get to the misfire tables and soften them up. That was it except for the flashing cel and no codes reported now. I saw a thread where you were having a similar problem. Short history. Put the car up for the winter with a full tank of 94 octane Sunoco and some Stabil. Took it down in late January, due to warm weather and started it. It ran like crap, and was actually randomly backfiring at idle and when you gave it a little more than 20% throttle under load it would hesitate and sputter but you could drive through it. That turned out to be 8 bad plug wires. They were supposed to be 350ohms and only 1 was under 1k, one was about 7k and the rest were above 2meg, the limit of my meter. I changed them and that fixed the hesitation but not the backfire at idle. That turned out to be fouled plugs from the wires. I installed a new set of TR6iX's, gapped at .045". I have around 520hp at the crank. That cured the backfiring, but now I have this uneven ltft at idle and I do believe it is misfiring or poor combustion. I am swapping the coil packs. It's possible I could have hurt a coil or 2 from running with those bad wires for a while. The P0300 was the only code I got except for a Crank Position Not Learned when I did the upgrade. I did a CASE relearn on that and stopped that one. One other thing, I did a cylinder balance test and all cylinders were almost 100%. No one cylinder was less than 2% less than another. I am also building a dash with the misfire code counters, not sure of the PID, it's on my laptop. I am going to log them and see where the problem lies if I can from that and also to see if it switches sides when I swap the coil packs.
Sorry for the long answer, been working on this for a while and I wanted to give you all I had.

[ArKay99]

A friend had a similar problem. He later found his O2 sensors were swapped left to right. Car ran like crap and threw codes.

I was under the car this weekend and the sensors are not crossed, unfortunately, I've seen that one. Thanks, I wish it were so.

[ArKay99]

I found the problem. It turns out the Jesels's were contacting the retainers when I first installed them. I undercut them and thought I had undercut enough. Not so on several of them. When I removed them after exhausting all other possibilities, a lot of my retainers had scratches on them, and the exhaust valve rocker on #8 had a small indentation the shape of the retainer on it. I took them off and put a set of Harland Sharp's on and the trims came back in line. The valves must have not been sealing properly, especially on #8. I hope my guides are ok now... So much for 'bolt ons'.

[TAQuickness]

glad you figured it out. I'm having a hell of a time trying to resolve a lean left bank. seems my manifold is leaking a bit at #7

[ArKay99]

glad you figured it out. I'm having a hell of a time trying to resolve a lean left bank. seems my manifold is leaking a bit at #7

I did this with mine, it seems to have helped. http://www.ls1tech.com/forums/showth...+manifold+leak

[joecar]

I did this with mine, it seems to have helped. http://www.ls1tech.com/forums/showth...+manifold+leak

That is quite clever.

[TAQuickness]

That is quite clever.

Indeed. I'll be giving that a shot tonight.