Q: why does my engine still stall after cleaning distributor cap, replacing air cleaner, fuel filter and spark plug.

Cleaning your distributor cap is not usually successful. The cap can have problems that cannot be seen with the naked eye. It should be replaced along with rotor, spark plugs, and spark plug wires. The description of your symptoms certainly seem to be ignition related, but fuel supply could be an issue.

I would use a test light to short each cylinder one at a time to isolate which cylinder is misfiring. It could be all of them. You will want to insert the test light between the boot and the wire at the distributor cap or spark plugs. Do not pierce the wires or boots. You need to make sure the tip of the test light slides between the boot and plug wire. The cylinder that doesn’t respond, or responds very little, is the cylinder or cylinders that is not firing.

Once I know which cylinder or cylinders are missing, I would inspect the spark plug, do a compression check and check to see if the injector is firing. Here is a fuel injector tester, this is the one I use. It works surprising well. Depending on what I find up to this point, I might check fuel pressure and compression check every cylinder. It is possible the timing belt has jumped a tooth or two. If you haven’t already, you should check the ignition timing.

If you need help, book an appointment with a certified technician, like one from YourMechanic. One of our mobile experts will be able to come to your home and diagnose the misfiring engine firsthand.

Good luck!