I have a 1997 cavalier and I am getting a p304 code, misfire cylinder 4. I changed the plugs, wires and coils. I think it might be a fuel injector problem. How do you remove and test the fuel injectors? Also I hear a clicking noise for about 30 seconds after I turn the engine off I think it might be the fuel injectors still clicking. could this be part of the problem?
If you really want to get into pulling injectors then go to an auto parts store and pick up a basic repair manual - Haynes or Chilton’s for about $20. It will tell you how to pull the fuel rail and injectors. It will also tell you how to check the electricals. (The most straightforward thing to do btw is just to swap the #4 with another and see if the misfire follows the injector.) While you’re getting a manual, inquire about a fuel line disconnect tool for GMs.
Before you go get into all of that you might just run through a shop (or find a buddy with the right tools) and have the compression checked. Ruling out mechanical issues first is never a bad idea.
I agree with checking the compression. If a cylinder is going down you can throw parts at it until a week from Wednesday with no improvement at all.
Thanks for the advice, I checked the compression with a compression gauge and all four cylinders have good compression. The strangest thing though, after performing the compression test now the engine won’t stay running,it runs for a minute then shuts off like it is running out of gas. It stayed running before I did the compression test, now all of a sudden it is like it isn’t getting enough fuel.what could I have messed up to cause this? I had the fuel pump relay out while I was doing the compression test. could this have done danage to the fuel pump?
It is very unlikely that anything you did damaged the fuel pump. It is plausible, however, that your fuel pump has been on its way out all this time. You need to put a pressure gauge in it to see what is going on with the fuel pressure.