Symptoms of Fuel injector problems.
Other injector problems are clogging and uneven spray patterns... you can remove the entire fuel rail and lift it above the cold engine... then have someone turn on the key and you watch for the spray pattern at each injector... you get a wide fan with mist...you can do them one at a time if you wish... just unplug the harness from each injector and repeat it over a small glass jar and watch and compare how they all play out...
or assume they are old and grimy and have a injector purge performed, their have bee good results with the chemical injected directly into the fuel rail and pressurized out to clean up the gum
good luck


