Car is miss firing on cylinder 3. It uses alot of extra gas. It can barely pull hills.engine jerks when starting car. I have bought and put on the car a new fuel injector,spark plugs , wires, coil pack,fuel pressure regulator and ignition module. What else can I do!?
My car has 200000 miles.
My car has an automatic transmission.
If electronics and fuel supply have been ruled out, the next possible cause is a mechanical issue. Have a compression test done across all 4 cylinders. If #3 is lower than the other three cylinders, it is possible there is a damaged valve or piston/rings.
Have a certified technician, such as one from YourMechanic, complete a misfire inspection at the convenience of your home as another possibility is that there is no signal to cylinder #3 from the PCM. The PCM can be faulty and/or a break in the wiring harness between the PCM and cylinder #3.