First drive L92 with VVT and 4L70E LOG

[gmh308]

Current TCM with a speedo factor of 2.87.

Thanks!!

Logging V2
PID KMH VSS_M = 68
PID KMH VSS=88 according to V2. Not sure what difference is between the PIDS.

Great to see you up and running!

Are you using a regular speedo?

Interesting to see the difference between the DMA PID for VSS and SAE PID. Ross might confirm, but I would expect that SAE VSS is derived from the DMA VSS PID. Maybe the various speedo calibrations factor the DMA VSS PID.

Cheers.

[Taz]

Nice to hear … you’ve been working at this for a while now … had to have been frustrating.

Replacing the transmission solenoid seemed to eliminate the P0787 DTC. Bringing the actual vehicle speed and calculated vehicle speed into reasonable agreement, let the “coarse” TCM tune actually begin to control the PT shifts.

I’m going to guess that now that the transmission is shifting, the TCM tune will need to be polished. Probably displays both too harsh, and too soft qualities - depending on speed / gear / TP.

At least you finally know the transmission is mechanical sound, and future refinements will be tune based.

Congratulations !


Regards,
Taz

[68problemchild]

I have kept the original 68 speedo so its cable driven from the tranny. Currently it needs a new gear since the 1968 speedo reads 61MPH at 50PMH.

The Logger is correct on V2 though. I looked at the GPS on my cell and VSS_DMA is right on. The regular VSS pid reads 10-20KMH higher than actual.

When VSS_DMA = 66 KMH
VSS= 88 KMH

Here is the working tranny tune

2008 24239927 Patrick Camaro Revised 8Dec10 - all previous mods - plus aggressive PT shifts - sp.tun

[68problemchild]

This is a quick log with Taz's pids followed by long log with the closest pids I could program into V2. Taz pids do not seem to log the cam timing. Open to ideas here.

Car VSS seems pretty spot on.

Tranny shifting into gears and downshifting just fine.

WOT second gear really breaks loose on the tires.

I am still getting the DTC P0011 on the cam timing but I am almost certain its the cam rev limiter I put in. I may set it to no mil.

Also I am still getting bank lean errors. Until I get the O2 back from innovate, any way to richin it up a bit? I would rather go too rich than too lean.

Thanks for the help guys. Taz the board says the last log is too big so I will send it email.

[Taz]

Hello 68problemchild,

Nice to see you making progress. As I have indicated in previous posts - Gen III guy - have never tuned a VVT Gen IV. I had further indicated there appeared to be 3 options for cam timing / angle PIDS - suggested beginning with the generic PIDs, and if these didn’t work, moving on to the other optional PIDs until the correct ones were located.

If memory serves, the remaining (untried) PIDs are labelled “intake cam” and “exhaust cam” - try each set of those separately, and see which ones are correct (if any) for your L92.


Happy Holidays,
Taz

[68problemchild]

Thanks Taz will do.

I am just so happy to be driving!!

[68problemchild]

OK, I just looked at my most recent long log with the pids. The max commanded in the run was 19 because I had done some mods to that file to cap it. Problem is actual cam never gets farther than 6.2 degreees advance.

Now the cam had built in advance of 5. Not sure if this matters. I know how to adjust it but not if its capping out at 6? Anyways, thanks to Taz I now know the phaser is not really functioning. It does have a cam limiter but this should only limit it a few degrees.

[Taz]

Took a look at the large log you sent me - nice job getting the cam angle PIDs working. I agree, your cam appears to be mechanically limited to around 6 degrees of advance, while the ECM is commanding 19 degrees of advance - which is generating an error of 12 degrees or so - setting the DTC.

The purpose of B7930 (Cam Position ECT Multiplier) appears to restrict cam advance when the engine is cold and under light load.

You have about 6.2 degrees of cam advance, that’s about 32% of what the ECM is commanding (19 degrees). Try setting the maximum values in B7930 to no more than 0.3200 - anything less than that don’t change - anything greater set to 0.3200.

This may eliminate the DTC being set.

I updated the test drive PIDs I had sent you with the correct cam angle group. This should help log data directly applicable to the cam angle and shifts.


Regards,
Taz

[68problemchild]

Here are two logs of the 2nd tune. (With VSS and slip test active) No dtc's other than P0011.

First to second is still harsh only at times but other gears seem fine.
WOT, chirps into second gear.

Still some rpm spin in first and second gear while car is in motion/slippage.

Tried to hold TP as best I could.

Thanks!!

[Taz]

Downloaded the logs … will have a look when I get back home later this evening.

If the ISS and trans Slip Test were active (had not been previously), and no DTC was set - it’s possible the slippage you are feeling currently is the TCC locking / unlocking. I recall when we were working on just getting the trans to shift at all - the low %TP and TCC parameters were modified.

Good job … any progress is good progress !!


Regards,
Taz