i found the engine number for the car i bought 4a-f engine this is a 0 interference right. i should change the timing belt asap?
Yes, start by checking on the belt right after checking to see if it is an interference engine. Next look up the recommended maintenance and get it all up to date. Likely it did not come with reliable evidence that all the maintenance has been done so have it all done (plugs plug wires, oil change, brake fluid change brakes checked If automatic have the fluid changed (not flushed) and the filter cleaned or replaced. Consider a new fuel filter cabin filter if it has one?.. etc.
To ok4450" '88 SR5 = 4A-FE.
Yes, it is interference fit, and yes, you should consider changing it if the last change date is unknown. Same for all the engine, transmission, and rear axle fluids. Just change them and keep track of the change intervals from now on.