I have a 1991 Previa LE. Runs great on the road but stalls at lights, intersections etc. anywhere I slow down and stop after the engine is warm. The only way to keep it running is to put one foot on the brake pedal and give it constant gas with the other.Just had a tune up: and spark plugs and wires,distributor rotor and cap,fuel filter and valve cover gasket set.Did not help the problem.The check engine light is not on. Really can't drive it anywhere but the open road anymore due to constant stalling.Where to go from here? Any ideas would be appreciated.

Try checking the alternator and the battery, you might have a weak battery and a alternator going bad... and may even be a weak belt.

id hate to see you spendind all these money on a tune up and it ends being an alternator, i had a similar problem when one of the alternator wires wasnt connected properly to the alternator, after replacing it and it made my car stall and actualy it would DIE if i let of the gas...

I had exactly the same problem with a 92 previa. I found two faults. The stalling was due to oil in the distributor. It was leaking through a worn rubber on the distributor itself. Then the constant restarting at every set of lights damged the fuel pump so it wouldnt start at all. I bought a used distributor for £90 and a fuel pump for £25. Worked like a dream after.