I have a 1991 350 SDL (original owner) with 148K miles. It's been a wonderful car.

Have a rough idle issue now. One shop wants to start with new calibrated injectors another wants to replace the nozzels and recalibrate the original injectors. The shop that wants to replace the nozzels says the new injectors are assembled in Mexico and are not very good.

I could use some input on what others have experienced with this issue.

Thank you.