I have a 305 TPI with a random misfire. No SES light and the car isn't giving me any codes. The Distributor cap and rotor along with the plugs and wires are all about a year old. The misfire is only noticeable while the car is at idle in either park or drive. While driving you cant notice or feel when the car misses out. Twice I noticed when driving around 1500 RPM the needle spiked and jumped around for a minute. Usually when the car starts it stumbles for a second then idles a little shaky. Last week on Saturday I dumped some fuel injector cleaner in the gas tank then drove the car to the gas station filled the tank then parked it. The following Thursday I went out started the car it fired right up didn't stumble and idled beautifully and ran very well. Could
I be looking at a possible fuel injector problem.

 

It's very possible, clogged or bad injectors will cause a miss just as easily as an ignition issue.