PCS trans controller + 4L80E best route?
04-17-2011, 10:19 PM
#21
When you say splice into the vss at the rear of the trans, your are referring to the VSS 2 pin plug that comes off the vss to the prewired 4l80 harness that runs back to the PCS box correct?
If so, that is how Tom's2005gto has the car wired currently. It is piggybacked from the 2 pin VSS output on the trans, over to the signal wire to the factory vss input at the PCM. This does not work. The speedometer will read relatively "close" to correct speed, but it does not hold a consistant reading, and if you stay running a constant speed, the speedometer will just drop to 0mph until you slow down or speed up.
As far as ppr settings, at 40, it's is No Where near accurate.
Any insight into this? It's a nagging problem for ALOT of Gto owners.
If so, that is how Tom's2005gto has the car wired currently. It is piggybacked from the 2 pin VSS output on the trans, over to the signal wire to the factory vss input at the PCM. This does not work. The speedometer will read relatively "close" to correct speed, but it does not hold a consistant reading, and if you stay running a constant speed, the speedometer will just drop to 0mph until you slow down or speed up.
As far as ppr settings, at 40, it's is No Where near accurate.
Any insight into this? It's a nagging problem for ALOT of Gto owners.
also, double check that it isnt backwards..
the VSS isnt any different than the rest of all GM transmissions..it is a 40x reluctor on the automatic transmissions
it needs to be the one at the rear of the trans near the tail housing
you will need to make sure the tune shows 40 Pulses per rotation and the proper pulses per mile..
Example:
40 pulses per roatation * rear gear for pulses per rotation
inches in a mile / inches of tire circumference = total tire rotations
tire rotations * Pulses per rotation = pulses per mile
40*3.46(05gto rear gear)=138.4 pulses per rotation
63360 inches in a mile/tire size in inches(stock is 24.93 on an 05 gto)=2541.5162 =
2541.5162*138.4 = 351745.84208 pulses per mile
04-18-2011, 07:38 AM
#22
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high side and low side are both tied in. Low side (reference) helped when it was tied in, but the speedometer will still go to 0mph when you stay at a consistant speed.
The Data side of the car will read speed correctly with this wired in, but the cluster does not.
Reading speed via HPtuners we are within a tolerable range (+/- 1mph). But the cluster does not operate properly.
The Data side of the car will read speed correctly with this wired in, but the cluster does not.
Reading speed via HPtuners we are within a tolerable range (+/- 1mph). But the cluster does not operate properly.
04-25-2011, 09:39 PM
#24
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I had to buy the PCS recommended USB adapter but it does communicate reliably now. With a few keystrokes, it even goes threw the gears. The software is a bit boneheaded but, it is giving me full control of everything I want to do and I can see my way threw to a perfect shifting trans once I have enough time to fully sort it. The car went around the block and grabbed all four gears as well as locking the converter on the first try. That is ALOT more than I can say for the previous AEM engine/trans control that was on this car. Now, to see if I can sort the delayed reverse engagement from the Rossler transbrake without a PRNDL switch....
04-25-2011, 09:44 PM
#25
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04-16-2014, 07:54 PM
#26
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Sorry for bumping an old thread but can someone tell me what would be wrong? RPM is off by double on the PCS controller. I haven't changed anything in the tune and it's set to 8 cylinders. I only need 3 inputs for the car to shift according to RPM. RPM, TPS and VSS. TPS is kinda close I guess. Driveline is still apart and just hooked it up to the laptop to see if I got the signals.
I went directly to the PCM (VSS, RPM) and TAC (TPS) to get these signals. Car is a 2003 Z06.
I went directly to the PCM (VSS, RPM) and TAC (TPS) to get these signals. Car is a 2003 Z06.
04-16-2014, 07:55 PM
#27
set it to 4 cylinders instead of 8...
GM tach output is a signal for a 4 cylinder...
setting the PCS controller to 4 cylinders will fix it.
under "Transmission Setup"
Speed Inputs / Gearing Chart
the top right value...Number of Cylinders...Change it to 4
GM tach output is a signal for a 4 cylinder...
setting the PCS controller to 4 cylinders will fix it.
under "Transmission Setup"
Speed Inputs / Gearing Chart
the top right value...Number of Cylinders...Change it to 4
Last edited by soundengineer; 04-16-2014 at 08:08 PM.
