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?
Set it higher. For example, if the 02 sensors are 3X the distance from the exhaust ports then try going 3X higher.
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
Last edited by troutdog311; 10-18-2015 at 06:34 PM.
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?
Well we took the car out today. Without resetting BLMs I did a 2-3 min warm up. I usually let it get in CL before I drive out but we were in a little hurry. It was a cool morning and took much longer to get in CL due to temp. It drove so good I mean very smooth getting up to speed even had very responsive throttle and nice idle. I didn't get on it but there are a few stop signs here and was just amazing pulling off from a start. I'm sure you know what I mean by this but I have a very good ear. I could really tell every cyl was hitting just right at a 2200-2400 cruise and no abnormal flutter in the seat of your pants. I have an amazing fiance that has been so supportive and very knowledgeable of the basics of tunerpro. She is my copilot and very good at calling out BLMs, Cell, Loop and what not.
Just as soon as I noticed the flutter/surge she calls out CL mode commenting what did parameter did you change lol I'm like nothing. Come to a stop sign and idle sounds odd like it's not as loud and oddly smooth that I know may sound weird but she even noticed this. Pulling off I had to feather the throttle to get the car moving and fully let off clutch. It was a 30 min drive to or destination. The surging did get better halfway there but not to my satisfaction. Idle and stumble from a stop also got much better but again not to my liking with a very rich exhaust smell. As we pulled up to a stop it was very rich smell BLMs at 108/110. I had to hear the ole lady complaining with " My clothes smell like exhaust" lol.
Getting ready to go home I decided to use Scan9495 to reset BLMs and lock in OL, and it was just amazing in every way. Throttle, cruise, idle and starting off from a stop just great also. We did notice a slight rich smell at a stop but nothing like in CL.
I don't want to deleted out CL "yet" in tuning because I feel like I'm just band-aiding the problem and will bug me till I die. Like I've stated this issue just started a few days ago with no change in tune. After flashing or BLM reset I have made sure to get at least 40 or so hits in each cell that it will go in anyway before making decisions on the tune currently used. O2's look great seesawing high/low like twins. I have noticed that the BLMs on right side is 5-7 higher than left at times though the ECM evens these out in a matter of seconds. I just wanted to tell you guys about today in hopes of giving more info that help me find what the heck in going on.
Thanks for helping
Basically it can only be once it goes into closed loop the computer is pulling or adding too much fuel for what ever reason. The only thing that has changed is the outside temp is cooler and have read the SD mode can roar it's ugly head when the outside temp changes. It could be O2s but they are less than 4 months old and receiving batt volts. It could be exhaust leak but I have replaced the header and collector gaskets. I have listened with a hose to my ear for leaks and can't hear any. How sensitive are these cars to exhaust leaks. I hope a leak smaller than a needle don't effects it.
I'll be playing around later and let you guys know what I come up with.
BLM <128 means the PCM is removing fuel. The fuel can't be rich with the BLM @ 110 if you started out with the fuel good and the BLM @ 128 while in open loop.
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