LS1 manual to auto reflash and basic tune to get me going!

[Taz]

Couple of things ...

Please post your current tune.

The front (toward the engine) VSS type sensor on a 4L80 is the ISS (input speed sensor) - this is used for Slip diagnostics. The rear (toward the tail stock) VSS type sensor is the VSS - this provides the PCM with vehicle speed.

If the VSS sensor on your transmission is absent (sometimes will have a blank plug / cover installed) - this will cause issues - as the PCM will not be receiving a VSS input.

Options include - adding the rear VSS sensor to the transmission, or if you have an accurate cable speedometer, adding an in-line pulse generator and adjusting the tune according to show true vehicle speed.

I prefer to run an actual 4L80 segment (if available) than to run the 4L80 with a 4L60 tune (using a relay).

[ZAPPA]

LS1B zappa stock tune.vats disable_0000.ctz
I appreciate any help! Ill need to find another speed sensor. will it affect the ecu if im in 4 low and the spped sensor isn't in the transfer?
Cheers in advance
Karl

[Taz]

With 512Kb PCMs the application of 4WD in OEM vehicles grounds both C2 (Red) pins 16 & 19 (one is the 4WD Low Signal, the other is the Front Axle).

This is what "tells" the PCM to use the 4WD Low portions of the calibration. The PCM then uses the Transfer Case Ratio to adjust the shift speeds, etc.

You need to wire these circuits (if you have not done so already).

Your 512Kb tune uses OS12225074 - which is very similar to the North American produced Camaro. There are a few issues though. In OS12225074 the 4WD option is disabled, and the Transfer Case Ratio is set to 0.000 (don't bother looking - these parameters are not in your version of the software). Also, there is no 4L80 segment for this OS.

Your options include:

• use a Camaro OS - which allows for a 4L80 segment swap
• use your current OS - which would necessitate using the relay method to operate the 4L80 (with the appropriate changes to the 4L60 calibration - gear ratios, shift speeds, etc.)

Once you decide which option you prefer, I can help further with the tune.

[joecar]

If the PCM originally drove a 4L60E, then you will have to also modify the subharness (in addition to swapping the segment and/or the OS)...


http://forum.efilive.com/showthread....l=1#post196234

[ZAPPA]

I've tried that 2 different ways joe ,but without doing segment swaps which I was told would work.
There is an express van 2002 5.7 with 4l80. could I use this?
When I pull up another tune with the 4l80 it tells me that it not combatible. Do I need to re flash with a complete new os , one the same as the 4l80 and then do the segment swap

[joecar]

Without doing the segment swap (i.e. just modifying the harness, * see below) you should be able to get it to work...

but you do need a 4L60E tune file that matches your PCM (i.e. same as PCM would have had for an auto trans).



* modifying 4L60E harness to drive a 4L80E:
- remove the 3-2 control signal;
- invert the 2-3 shift solenoid signal (using a relay);
- use the TCC Enable (On/Off) signal to drive TCC PWM.

[ZAPPA]

2002 Chevrolet Express (4L80E) Van Automatic L31 5.7 Litre (12212156) (1)_0000.tun
can I use this one as a reflash and turn on the 4wd side? Its the only ls1 with a 4l80 I can find
Cheers

[ZAPPA]

Ill go over that post again that you linked. it seems to lock me in second and run rough until it gets more throttle , I can hear the relay clicking when I back off.
My mate who is an auto sparky is coming down next week, all this will mean a lot more to him than me! Im just trying to get the right info so we can sort it out in the 2 days that he is here
That's exactly what I have done, although there is only 1 speed sensor in the box. it was from a suburban. only the front one is in there, the rear is plugged.

[Taz]

2002 Chevrolet Express (4L80E) Van Automatic L31 5.7 Litre (12212156) (1)_0000.tun
can I use this one as a reflash and turn on the 4wd side? Its the only ls1 with a 4l80 I can find
Cheers

That is not an LS1. That is an L31 Vortec (old Gen I 5.7L with a 4x CKP) - not sure if these were ever available Down Under.

It is not compatible. If you want, start with a 2002 Camaro tune, then swap in the 4L80 segments (calibration & diagnostics) from a 2002 LQ4 6.0L truck tune.

[joecar]

Show us a diagram (that you drew) of the harness mod (show how you connected the relay).