Tuning question for 730 ECM

[Dave Zug]

A car with a bad TCC solenoid does NOT exhibit the symptom, IME. Also if you
take the connector off the trans.

----- Original Message -----
From: <gcwestph at erols.com>
To: <gmecm at diy-efi.org>
Sent: Saturday, October 14, 2000 7:16 PM
Subject: Re: Tuning question for 730 ECM


> Shannen Durphey wrote:
> >
> > Tim,
> >
> > Are you sure it's only a speed related TCC apply?   What happens if
> > you disconnect the VSS?
> > Shannen
>
> I've seen the same thing in my '87 IROC and a friend's '91 Z28 using a
> scan tool while making 1/4-mile runs.  Watched it both in rpm and TCC
> lock-up command.
>
> Greg Westphal
> '87 IROC
>
> > timsiford at hushmail.com wrote:
> > >
> > > Blade,
> > >
> > > That is the Mandatory Torque converter lockup point. No matter what
...
> > > the ECM commands TC lockup at that MPH. If you plot your Vehicle Speed
you'll
> > > notice that the speed still increases even though your RPMs drop.
> > >
> > > The newest TC calibration file has a setting in the ECM Constants
section
> > > called "TCC Unlock Prevention Speed Threshhold". That should be the
mph
> > > that you see your RPMs dropping. Only problem is ... even if you bump
up
> > > this setting it doesn't seem to work  I verified that TC is using the
correct
> > > BIN addresses. They are 100% correct ... but, I think that I am still
seeing
> > > lock. Modify this parameter to a higher mph ... like 115mph. Burn a
new
> > > chip and then try again. Let me know if it works for you.
> > >
> > > Tim
> --------------------------------------------------------------------------
--
> To unsubscribe from gmecm, send "unsubscribe gmecm" (without the quotes)
> in the body of a message (not the subject) to majordomo at lists.diy-efi.org
>
>

----------------------------------------------------------------------------
To unsubscribe from gmecm, send "unsubscribe gmecm" (without the quotes)
in the body of a message (not the subject) to majordomo at lists.diy-efi.org