94 EE surges in SD closed loop at cuise and acceleration

[troutdog311]

I have been tuning for about 4 months now with great success though I have so much to learn. I switched to SD 2 weeks ago due to how good it runs with no split BLMs and power at WOT. I have been using VEMaster and has really improved cruise below 3k. It has been cruising smooth as silk until a few days ago. After this issue started I noticed the motor runs very smooth after I flash a tune until it reaches CL mode then it starts surging and slight stumble off idle. BTW these tunes are for speedo, PE and such nothing to do with cruise. Even after 40+ hits in each cell and I force OL it still does this same issue. It's only after a flash tune or I reset BLMs it runs so smooth then the second CL come into effect it surges and stumbles off idle. I can reset BLMs and lock it in OL and we are good then I remove the forced OL switching to CL it does this yet again.
I must be missing something and at a loss of ideas to fix this issue. I will say that my BLMs are great in CL besides at idle cell 16 which are 108/108 but I believe this is a false reading without the use of wide band O2s but thats maybe another story. I just don't see how BLMs can be 126-130 on both with a surge. What you guys think, Thank you

94 LT1, LT4 heads, LT4 hot cam, Lt4 intake, long headers, stock TB, new O2s, new fuel reg, new opti and new other crap

[lionelhutz]

It sounds like it's going lean at idle. Do your O2's have a good source of power for the heaters? Did you modify the integer delay time for the extra length in the headers? O2 sensors will read a false rich for a bit as they cool down from operating temperature hence my question about the heaters. I've had the same problem before. Come down to a idle and the engine starts running like crap and I traced it back to the O2 sensor not working as it cooled down a bit.

[troutdog311]

Thank you Lionel, the delay is actually one thing I havent even thought of since the first times I started tuning. My settings now for O2 INT Delay are:
800
275
200
175
162

I never thought that INT Delay would cause an issue like I have but it does make sense. What do you recommend I set it as for a start, I'm guessing lower?

[lionelhutz]

Set it higher. For example, if the 02 sensors are 3X the distance from the exhaust ports then try going 3X higher.

[troutdog311]

Thanks the O2s do have battery power and have actually checked with infrared temp gauge after 30 sec or so of key on only and are same temp. I was guessing INT delay lower because of the online bins that I have for comparing are lower. The other thing thats got me is it was running great with these delay setting until few days ago. I understand we my have rough running after a flash until the ecm gets enough hits in each cell and learn.
I do believe I'm getting a false rich at idle and may actually be lean but header temp at idle are in spec and playing with Steveo's EE hack has kinda confirmed this. Header temp are a little off as far as individual temp and haven't messed with Ind Cyl Fuel Trim yet. I do remember messing with this parameter before and that did cause a surge. I set ind fuel trim all to 1.00 as of now and has been running fine but again that's another day. I'll give the INT Delay a test today, Thanks

[lionelhutz]

Yes, I doubt the delays will fix it. But, something is off with the closed loop operation because what you're describing sounds like its tuning itself to the lean side. What are the logs showing?