My 454 Rebuild

[L31MaxExpress]

No, it is always slightly rough hot or cold. You can feel the miss more when cold vs hot when driving.

Have you looked at misfire counts with a scan tool? If it is misfiring that consistently it should show misfire count or counts.

 

[Spareparts]

it does show misfire counts. Seems to be random and will not set a code and none in history.
When cold i have seen cylinder 4 at 40 and the next day be 2 but say cylinder 8 will have none. The next day it will act different.
When warm it will show a few random misfires on a couple cylinders like 2 misfires then they go away.
Since i can not find anything mechanical really wrong maybe it is electrical.
The water temp sensor on the front of the block is reading correct.
Kinda interesting but the IAT never shows the actual temp before i start it in the morning. If its 25 out it will read 35 and always warmer than actual air temp by at least 10 degrees even when warmed up so i replaced it. New one acts the exact same way.
Timing starts at 25 and goes up as rpm increases. I never see any knock retard. Injector pulse appears even on all cylinders.
Since i had 2 bad plug wires with the new AcDelco set i suppose i will replace them all this morning with a new set and see what happens. If new sparkalator wires cures it ill be happy but pis*ed that i spent two months and untold time on something so easy.

 

[Spareparts]

Well i can't say new plug wires cured it totally i can say it is WAY better though and once off idle it feels gone. Never in my life have i had bad new plug wires but they were 99 percent of the problem. So i guess i'll call it a win i'll also give it a few days for the ecu to relearn.
Random misfires are also near 0 now
I also suspect the compression checks i have done with different cheaper gauges always showing low. Wish i could get my hands on a good Snapon gauge.
If all seems good in a few weeks i'll put the 0411 back in and the adjustable valve train/roller rockers then look at buying HP Tuners but dam* it's expensive!

 

[BNielsen]

Well i can't say new plug wires cured it totally i can say it is WAY better though and once off idle it feels gone. Never in my life have i had bad new plug wires but they were 99 percent of the problem. So i guess i'll call it a win i'll also give it a few days for the ecu to relearn.
Random misfires are also near 0 now
I also suspect the compression checks i have done with different cheaper gauges always showing low. Wish i could get my hands on a good Snapon gauge.
If all seems good in a few weeks i'll put the 0411 back in and the adjustable valve train/roller rockers then look at buying HP Tuners but dam* it's expensive!

10/10 recommend getting HPTuners ASAP. It's not getting any cheaper, trust me on that one. I 0411 swapped my truck in 2019, told myself I'd wait for HPTuners and it must've gone up $150 by the time I finally bought it

 

[L31MaxExpress]

10/10 recommend getting HPTuners ASAP. It's not getting any cheaper, trust me on that one. I 0411 swapped my truck in 2019, told myself I'd wait for HPTuners and it must've gone up $150 by the time I finally bought it

If I did not already own HP Tuners, I would not buy it personally. I would be using Universal Patcher, TunerProRT and PCM Hammer. I actually find myself using it more and more anyway even owning HPTuners. HP Tuners does less but is a little more user friendly. I have not bought a HP Tuners VIN license for a P01 or P59 in close to 6 months since I have been using the Open Source stuff. With Universal Patcher you can either use it for Editing or export a definition file for TunerPro. Universal patcher also has the ability to do segment swaps, add lean cruise or even flex fuel on the P59s. I have a DBC P59 file for a 4x ignition reluctor and the vortec distributor setup.

You can download the programs I mentioned and get an OBDLinkSX OBD2 USB cable for $50. With that you actually have more editing ability than HP Tuners provides.

 

[Spareparts]

Been thinking LS droid, Universal patcher, PC hammer, Tunerpro. I have them downloaded. I just need ODBlinksx.

 

[Spareparts]

Problem is the 0411 i have is running HP Tuners so unless i use that i basically have a 0411 brick.

 

[L31MaxExpress]

Problem is the 0411 i have is running HP Tuners so unless i use that i basically have a 0411 brick.

That is not a problem as long as the file is not tune locked and it is not converted to a custom operating system, like 2 bar or 3 bar speed density. As long as the access pin is still factory any software can read the calibration.

I have read my P59 a few times with PCM Hammer to use TunerPro to edit things HP Tuners does not have mapped out. Then reflashed it with PCM Hammer. Then re-read the file with HP Tuners and continued tuning. I had some idle stuff not available in HP Tuners that I had to fix converting from a manual trans to automatic. Some of the PID loop for controlling the idle speed in Park/Neutral was not populated and the PCM could not adjust the idle speed in Park or Neutral.

 

[Spareparts]

I asked Black Bear and he said he does not lock his tunes. Anyone i choose is free to edit it.

 

[L31MaxExpress]

I asked Black Bear and he said he does not lock his tunes. Anyone i choose is free to edit it.

I do not lock mine either. I feel only someone that is clueless does.