Chevy Z71 5.7 EFI->Vortec heads-CFSI-BlackBox PCM conversion. Trans wiring problem((

[LRT]

I still want to learn how to make an xdf

Much easier said, than done ...

Below is a JPEG from the BIN that you attached in post #12. Inside the red box, is the main Idle Table.

How do you find this ?

What type of data is it ?

What is the conversion equation ?

Is there an offset applied ?

These are just examples of what you would need to know and do to create an XDF file.

Attachment 10686

[Aksl]

I dont have all the answers (or any for that matter) but it seems when i had a vortec in my el camino (with black box) i still had to use a drac (vss buffer)...(had third gen camaro guages so i used the buffer box behind the speedo) IIRC i took the parking pawl from a late 4l60 and swapped into my 700r4 in order to use the prndl switch from a 98 4l60e .....(maybe you don't need it?) i believe you would want to use the speed sensor in the transfer case (final drive and all) the four pin connector on the trans will be converter lockup control, there may be better ways now,but we just left the lockup control mechanical, wired through the brake switch and a vacuum switch. had to turn off a couple trans codes too ........ (the black box puts out a pwm signal for lockup, no good with 700r4 converter), im sure more knowledgable folks will chime in soon... Good luck, sounds like a fun project.

Hello skandolis, thank you for your help! So where am I at now, I connected the prndl switch to the underhood wiring, switched it to D, and it seems that now I got rid of the problem with truck trying to pull all time while I apply brake. I will make an adapter to install the switch to the axle out of the transmission, because if I instal the axle to the gearbox from later l460e, I will have to change all the switching gears system, changing it to cable instead of my, that uses rods.
I didn't yet find the drac, and don't yet know which pin to connect it to in my blackbox pcm when I will, may be when I do that I will get rid of problem I have now, may be you can confirm that my issue now is due to drac not connected. So the issue is, when I drive, and apply brakes and stop, the engine starts to loose idle and work unstable, like it's gonna go off, but it doesn't, it just like seem to choke. Can the issue be that drac not connected to my pcm cause this happening?

https://youtu.be/U51Qe9hKwdc

You can hear how it chokes on the video by the YouTube link above..

[Aksl]

Hello LRT, some time passed and i did make some changes to improove my trucks condition, but unfortunatrly i am still left with the problem of idle under load...

So what i did was:

- Wired the brake switch to the PCM C4 pin10. (no result)
- Wired the vss. (no result)
- bought and connected the PRNDL switch to the wirring. (no result)
- Made a new full exhast system, the old one seemed to have detonation of gasess. (fixed the detonation issue).
- Now it is is less than 10- degrees, but at warming up the truck still does not increase idle.

So what i ended up with is a better stable engine work, but still have the problem of idle under load. And noticed that it is not only when i put the gear in, but just standing on the Park or Neutral, the truck works just fine, when i start to spin the steering and the power steering is in action the idle starts to drop dramatecly and the engine almost stalls. So it happens at any load, not just on gear in..
I have checked and replaced all possible sensors, MAP, MAF, tepriture, lookd for vacuum leaks, Fuel pressure fine (onlyreverse fuel valve seems to drop pressure fast after shut off, but that is irrelevant with my issue), iddle control valve is fine (have replaced for new), fuel pressure regulater is fine, checked everything i could, there are no faults from the PCM...

By the way, my EGR is deleted in my vehicle, so it cant be it..

If anyone here run in to something similar, could you give some advise. Thank you.

LRT, you have mentioned that the Torque Management has been disabled, i guess this can cause the issue, cant it???

Thanks..

[89S10_Project]

You mentioned that the Idle does not increase from a cold start, and then decrease as it warms up. The Idle speed table does not cause a significant increase in Idle RPM until the ECT (engine coolant temperature) is less than 10 degrees Celsius, which it likely never will be during the summer months. The startup "adder" table will increase the Idle RPM between 15 RPM and 75 RPM (based on ECT), so this additional RPM will not really be noticeable.

I have to pop in here and comment on this-

I live in Charleston, SC- It doesn't often get under 10C (50F) here. I do recall when I had my 4.3 (which also ran off of a 7747 ECM) it would do a cold-start idle-up all the time- winiter, summer, doesn't matter. The truck would idle up to about 1kRPM and then after 20 seconds or so drop back to normal idle.

I swapped in a 5.7 using a 7747 (not the same ECM, but another ECM which had been in service in front of an identical drivetrain to my present 5.7/700R4 combo). I no longer have the idle-up on start. It remains to be seen if I will have it when under 10C/50F- I will update when it gets colder.

[89S10_Project]

...noticed that it is not only when i put the gear in, but just standing on the Park or Neutral, the truck works just fine, when i start to spin the steering and the power steering is in action the idle starts to drop dramatecly and the engine almost stalls. So it happens at any load, not just on gear in..

Just spitballing here, seems as I recall seeing a similar problem-

isn't there a pressure switch in the power steering system specifically to cause idle-up in response to actuation of the steering around idle speed, to resolve this sort of issue?

[Aksl]

Just spitballing here, seems as I recall seeing a similar problem-

isn't there a pressure switch in the power steering system specifically to cause idle-up in response to actuation of the steering around idle speed, to resolve this sort of issue?

Well sir, you r correct, but not all models have this valve/sensor on the steering.
Others like mine, use map and maf sensors to detect the load applied to the engine and add extra idle...

[lionelhutz]

It sounds like the IAC is not working. It should maintain the same idle rpm even when the load at idle varies. It might dip or rise a little as you shift in and out of gear but it should always return to the same idle rpm and not keep idling at different rpm's as the load changes.

[Aksl]

It sounds like the IAC is not working. It should maintain the same idle rpm even when the load at idle varies. It might dip or rise a little as you shift in and out of gear but it should always return to the same idle rpm and not keep idling at different rpm's as the load changes.

Hi, have tryed to replace the iac with one from a running vehicle, same atitude, steering turn, idle dropes, the truck almost stalls, shift to drive, same thing..((
When start to drive and accelerate a bit, the idle rises and drops spantanules, makes the truck pull and stall until I accelerate more, it like shakes forward and back... Don't know how I can explain more precise..(