I have already checked the cold start injector and the fuel injectors. Ohms and voltage and listened to them. Also looked for vacuum leaks. Timing is correct and voltage from the alternator correct. I don't know where else to look.
My car has 125000 miles.
My car has an automatic transmission.
The fuel injectors have internal filter baskets and thus the only way to clean and service them is to remove them from the fuel rail and send them to a lab such as Mr. Injector for ultrasonic cleaning on a specialized machine. During such service, the filter baskets in the injectors are removed and replaced with new filters, and then injector output and spray pattern is measured and documented. The fuel filter should be replaced and fuel pressure on the fuel rail tested. Check spark plugs, cap and rotor, and wires. If those components are "old", replace them outright. Also test coolant temperature switch, throttle position sensor, mass airflow sensor as well as idle air control valve for proper function. If the problem is still not resolved or you desire that a certified Mechanic, dispatched by YourMechanic right to your location, perform these steps, please request a rough idle/cold start diagnostic and the responding certified mechanic will get this resolved for you. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.
Have a car question? Get free advice from our top-rated mechanics.
Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing