Suzuki sidekick transmission - wont go into drive gear until warm

sounds like transmission ..weak internal pressures..failing torque converter... go to AAMCO or other for free diagnostic to confirm

You are going to need to have the transmission rebuilt.

Check your auto transmission levels. Slow, often jerky, gear shifting is often accompanied by a bit of a jolt when putting it into drive from park or neutral. When fluids are low the torque converter impeller has to work harder to get pressure up and therefore it is slower at shifting to the next gear . Low transmission fluids also lead to poor fuel consumption.

1989? When was the last time the Transmission was drained and new Transmission Fluid (oil) put in?
This Fluid (oil) loses viscosity and get particles in it causing additional loss in viscosity. I would go to even having the transmission drained and FLUSHED (cleaned) and new Fluid (oil) put in. Recheck the operation.
Boyles and Charles Laws are applicable here: (P*V)/T. Heat causes the Fluid to Heat and Expand (in molecules) but because of the limited sealed volume (transmission case) this increases Pressure allowing the smoother shifting and placement into gears.
Change the Transmission Fluid (oil) and have the Transmission Flushed (cleaning the insides) and your problem should go away.
Let me know if this helped, or if you have any additional information or questions. Feel free to contact me at FixYa.com!

do you mean wont disengage? does the pedal feel normal, or like its pushing nothing?cant put it in gear? or goes in gear but wont move?. if you put it in gear but car wont move, the clutch is toasted. if you can put it in gear with the engine off, but not when its running, check the clutch master fluid. if its low or out, then the slave or master is leaking and you will need to replace both. if the clutch arm IS working, and the pedal feels normal, sometimes you can put in gear, and start it with the clutch pedal depressed and drive it, and goose the gas to "break the disc loose"

Buy a bottle of Techron Fuel injector cleaner. It's sold in many grocery stores and all auto parts stores. Pour the whole bottle into the gas tank when you can fill up. Drive the car and don't put more gas in until the car is almost empty. That should fix it

needs a tune up

it will not move because it is low on transmission fluid, warming the car casues the fluid to expand therefore making movement possible. also fluid looses viscosity when heated so you may want to look a full fransmission fluid and filter change. But still, get your car warm and check the transmission fluid, i bet its low. Dont forget to rate.

Try some Seafoam brand trans tune it might help.
Even if it dosen't it's a cheap experment.

have known ignition systems to do that. as temp. increases resistance will change