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Engine Misfireing

The car has 75,000 miles the tank of gas was empty i added injector cleaner then filled the tank. It drove fine the first day. But the next day i was comming home from work and the engine began to misfire as if a spark plug or wire had stopped working. when i got home i tested each spark plug ad cable the were all working to factory specifications. You could tell that at idle the engine was misfirering. when you accelerated softly the engine could go through all the rpm without a hitch but if you pushed “normally” the engine will misfire. Now i use injector cleaner regularly and i fill the tank with fuel at the same place every time.

Injector cleaner won’t solve a misfire. You’re wasting money.

Is the CEL on? If so, what are the codes? Have the computer scanned if you’re not sure. Parts stores will do it free. It might tell you which cylinder is misfiring.

If I understand correctly it did not misfire before adding injector cleaner.

It’s possible the injector cleaner dislodged some dirt from an old, compromised fuel filter, which found its way to an injector.
It’s possible the injector cleaner made the engine run stronger with higher combustion pressure, which in turn overstressed an already weak ignition component.

I would test for spark strength and change the fuel filter if it hasn’t been done on time.

Injectors can fail electrically too…They are not dirty, they just stop working and act just like an ignition misfire. You can disconnect them one at a time and quickly spot a bad injector…