O
omega1940
Guest
I received an email from Joseph Arnone, whom I think is connected with Chris Petris or Corvette Fever. The email gave instructions on how to rewire the ECM harness to give a driver complete control over the 4+3 from the shifter button.
Earlier, I had put a jumper on the transmission O/D switch, and ended up with my 88 L-98 starting out without OD through the first 3 gears then dumping in to OD (assuming the right tempeture of 127 degrees).
Jospeh said to cut the A-7 tan/black wire 3 inches from the connector. Also, cut the C-7 tan/black wire in the same manner. I was not clear on which side of the wires to reconnect, so I first tried connecting the wires that came out of the plastic connector. I test drove and ended up with no overdrive at all, just 4 straight gears. The shifter button did nothing.
I then went back and connected the two cut wires that came down from the wiring harness. I left the two cut wires at the connector disconnected. I test drove the car and discovered that I had no overdrive on any gear until I depressed the shifter button. I thought EUREKA! until I disocvered that I had to hold the shifter button down or it immediately popped out of OD.
I then tried connecting the ends of the two wires at both the harness side and the connector side and it was the same as the situation just above. (Holding down the button to stay in overdrive.
I'm sorry to go on and on, but I've tried everything. I had put a jumper on the OD connector on the transmission (not the overdrive unit as one person said). This came pretty close to perfect because when starting the car it said out of overdrive until 4th gear then dumped down into OD automatically. I'm not certain just what to expect, but I have to believe someone out there has done this right and ended up with "complete control of the 4+3 from the shifter button.
Help.
Mike
Earlier, I had put a jumper on the transmission O/D switch, and ended up with my 88 L-98 starting out without OD through the first 3 gears then dumping in to OD (assuming the right tempeture of 127 degrees).
Jospeh said to cut the A-7 tan/black wire 3 inches from the connector. Also, cut the C-7 tan/black wire in the same manner. I was not clear on which side of the wires to reconnect, so I first tried connecting the wires that came out of the plastic connector. I test drove and ended up with no overdrive at all, just 4 straight gears. The shifter button did nothing.
I then went back and connected the two cut wires that came down from the wiring harness. I left the two cut wires at the connector disconnected. I test drove the car and discovered that I had no overdrive on any gear until I depressed the shifter button. I thought EUREKA! until I disocvered that I had to hold the shifter button down or it immediately popped out of OD.
I then tried connecting the ends of the two wires at both the harness side and the connector side and it was the same as the situation just above. (Holding down the button to stay in overdrive.
I'm sorry to go on and on, but I've tried everything. I had put a jumper on the OD connector on the transmission (not the overdrive unit as one person said). This came pretty close to perfect because when starting the car it said out of overdrive until 4th gear then dumped down into OD automatically. I'm not certain just what to expect, but I have to believe someone out there has done this right and ended up with "complete control of the 4+3 from the shifter button.
Help.
Mike