Currently I have a 1983 280zx with 3 speed automatic.
On drive 'D' all 3 gears are changing before 3000 rpm
When I go to 2nd gear manually I would get 5000 rpm
Anyone got any suggestion on what is going wrong

zx owner

 

There's a kickdown solenoid that is activated by a full-throttle switch.

The switch could be out of adjustment or faulty. The solenoid could be faulty, the wiring could be faulty.

Lets try to narrow things down a bit:
With the car off, depressing the throttle fully should result in an audible click from the pedal assembly (test #1). With the ignition on, you should also be able to hear the solenoid quite easily on the transmission (get someone under the car listening while you depress the throttle) (test #2).

Get back to us with the results...

Ben
Adelaide
Sth Australia
IZCC#1902
240Z L31ETT
L28ET MR30 Skyline
FJ20ET DR30 Skyline RS-X

 

A full throttle shift should change ~5500rpm, this can be modified, my turbo cars are set to 6000rpm.

Ben
Adelaide
Sth Australia
IZCC#1902
240Z L31ETT
L28ET MR30 Skyline
FJ20ET DR30 Skyline RS-X

 

Thanks Ben,
The wiring for the switch was disconnected.
Now I'm getting 5500 rpm on kickdown when in drive.
Any ideas on how I get more rpm?
I have a P90 head - port and polish
L28 block - stock
Pair of 2 "inch Jaguar SU's
268 cam
MSD ignition
extractors

zx owner

 

How do I modify the throttle shift?

zx owner

 

It has to be done by a workshop with the transmission out of the car & in pieces. I had several things done to my 3 & 4-speed boxes, kevlar clutches, raised max rpm, higher band clamping force & higher stall speed.

Ben
Adelaide
Sth Australia
IZCC#1902
240Z L31ETT
L28ET MR30 Skyline
FJ20ET DR30 Skyline RS-X