low BLM

[donf]

Post up the file of the drive. Did you get your fuel issues sorted? I would work on that first, then switch. In my timing tables the timing at wot does drop compared to the part throttle areas. Remember all this is not exact. Gm never released its code to the public. When I was trying to look at timing tables any retard number under zero would read -28899383 timing or some crazy number like that. That alone makes me doubt the integrity of the data. John from 1320 tried some code changes in his software to help. Its files use mostly the same as tuner pro, but the changes did not fix the problem. So many people think what they are seeing is in tuner pro logs are exact and the truth. A lot of this is a reversed engineered wild guess and it does have bugs.

[dhworkin]

11111.xdl11111 is the ride out of town.3333.xdl3333 is a back road, tried to be steady with the throttle. Yes fuel issue is fixed. I do see the 22.5 degree timing 0n the max retard history table and I don't like that, what could cause that? The only sensor not changed is the knock. All sensors where replaced with ac delco when I installed the motor, and they have been changed again because of me trouble shooting via throwing parts at it. I've changed distributor, pcm, coil, wires, driveshaft, axles, wheels, tires(twice), brakes(rotors, drums, pads, shoes, calipers, slave cylinders), steering box, all steering parts and the shocks. All of that work and nothing has changed (it still shakes and jerks like its a bad tire or it has a ignition miss).

[dhworkin]

vortec.binThis is the bin I used in the data log.

[dhworkin]

4444.xdl4444 should be the steady log.

[donf]

I looked at the 3333 and 4444 log. Its better but your fuel tables still need a little work. You could hook up the wideband now and use its data to better see whats happening. You will never get it to stay at 128 at all times but the lower kpa ranges are rich and the higher ones are lean. If the miss or jerk problem is under transition, it could be need more or less fuel under those conditions, but I would get the steady state tuning done a little better before trying to tackle that. Having someone ride with you to see what cells are active in the logger when the problem happens would be helpful too. It may not be that at all, all we can see is numbers on the computer screen, but its a start.

Your spark logs look pretty normal, including the crazy 23039.682 and 420 numbers in the cells, its just something that happens when $0D in tuner pro goes to retard and a pretty good indicator not to take the information all too seriously. I have no idea why you are hitting 22 degrees of knock retard in the lower cells intermittently. You will see the average in that cell is just over 1 degree. I would pull one degree from several cells in that immediate area and see if it helps. Your at 198/ 205 temperature in all runs so you might switch it to a 180 degree thermostat. The hotter the engine the more likely it is to knock. In the spark advance tables with my van I noticed if I was not steady with the throttle at all times what appeared to be happening is numbers from one cell get logged into another. The crazy numbers filling the table seem to be with large and sudden changes in the throttle. I do not know that for a fact, but driving like a grandma helped my spark table look a lot like it should. Having a helper watch the table to see spark retard max might be interesting too. If the 22.5 degrees of retard gets set when you have your jerk or miss or what ever is happening it could be a clue.

[dhworkin]

I got a 180 thermostat, my shield gas refilled and the rest of the weekend to work on my truck. Thank you for all the info. I finally decided to set it to stay in open loop and see what happens, most all problems went away. I don’t understand why but it’s good to know that it’s going get better. There is not much power in open loop but it doesn’t stumble, shake and shut off when coming to a stop. What sensors are not used when in open loop? I’ve checked all the wiring under the hood and will check for bad wires underneath when I weld in the bung. I might drop the transmission as well to install a torque converter with a little less stall. I never mentioned the torque converter when I listed the mods, would that affect the tune?

[donf]

The difference between open and closed is mostly in closed the computer is adjusting the fuel mixture. Do you have the wideband hooked up? The problem not happening in open loop is a pretty good indicator that your main tables still need work.