My 90 ls400 isn’t running right

[Alstef546]

Every time I start up my car it misfires at idle. Whenever I give it partial throttle it seems to backfire through the intake, I don’t know if it’s timing related  but the car is getting good spark. I replaced both coils, cam sensors, crank sensor and the plugs. I inspected the caps and rotors no problems there. The car also has trouble starting after driving 12 miles exactly. It cranks but dosent start. I’m completely lost any help would be appreciated thanks

[chc0318]

Any Diagnostic Trouble Code? Does the engine stop when you stop on the traffic light? If yes,  you need to check the EGR valve.

[Bykfixer]

How long since your last timing belt change?