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The best way to test is by swapping around coils to see if msifire moves assuming you have a specific misfire. Otherwise you will need to swap around injector to see if misfire moves.There are no specifications for resistance, you could check and compare them to eachother.
I replaced one on the no. 4 cyl. it indicated a misfire. the car is still running bad
The car is running choppy and I need to pinpoint either or or both are the problem. How can I check both to determine the problem?
Yes you can do resistance tests and you can try to listen for clicking injectors if manually supplying power/ground.
Also could it be the fuel pump? What is the PSI for the fuel pump on the rail?