L98 ECM question
07-24-2017, 11:48 PM
#1
Instructor
Thread Starter
L98 ECM question
As far as I know the computer in my 1987 Vette does not communicate with the auto transmission or rear end at all. New gears and new torque converter should not need prom programming. Correct?
Last edited by fast.asleep; 07-24-2017 at 11:49 PM.
07-25-2017, 03:29 AM
#2
Race Director
The ECM locks the torque converter clutch. That is the only output from the ECM to the trans.
There are different EPROM part numbers for the various differential ratios, so yes, that needs to be programmed.
The VSS (Vehicle Speed Sensor) has different gear ratios for the different differential ratios, so that is also a consideration. The speedometer will be off if the correct VSS gear is not used.
There are different EPROM part numbers for the various differential ratios, so yes, that needs to be programmed.
The VSS (Vehicle Speed Sensor) has different gear ratios for the different differential ratios, so that is also a consideration. The speedometer will be off if the correct VSS gear is not used.
07-26-2017, 02:58 AM
#4
Race Director
The 4L60E has an electronic VSS (reluctor instead of gears). The 700r4 and 4L60 have a gear VSS that interfaces with a gear on the trans output shaft.
Last edited by Cliff Harris; 07-26-2017 at 02:59 AM.