Hello Mr kilmer, my name is justin. I have an ae91 toyota corolla, it previously had a 4a engine efi and I changed it to a 5a efi eng and transmission, it worked fine until this year it started giving trouble to start after I did a paint job on it, I live in the tropics, once the car is parked overnight or more than 6 hours I have to try up to 4 times to get it started. and when it does start if i press the accelerator it would back fire and almost shut down. I have to wait a few mins then i can drive off with the engine hesitating. When it is warmed it starts better but if i press the accelerator it hesitates (worse with the ac on) and takes a while to rev up when on drive. To this day I have changed the fuel pump, filter, spark plug, brain box, distributor , serviced the injectors and nothing helps it is worse now, 7 attempts before it starts now. I like the car and i don't want to sell it. everyone I took the car to doesn't seem to know what to do I would greatly appreciate your thoughts on this matter. Thank you.
somany things can go wrong with such an old vehicle. but if it was after a paint job, check to see if they messed up wiring or got crud in the gas tank