[breaker19]

I have a misfire, #4, always #4, I replaced the spark plugs and I thought maybe the new spark plugs were bad so I bought new set and still it misfires, so I bought new wires and a new fuel injector and a new coil and still it misfires, so I bought another new coil, thinking maybe that new coil was bad and still misfires

Only happens after about 120 miles, then the light comes on, I clear it and 120 miles later, the light comes on again.

Any ideas what could be wrong?

Someone said the coil is bad, but I bought 2 of them, could 2 coils be bad?

 

[red99]

You don't state the year or engine code. I assume that you have a single coil assembly for all 4 cylinders.

The misfire codes come from the knock sensors. One of them could be bad. Try swapping them and see if the misfire moves to another cylinder. If so, probably a knock sensor is bad.

 

[breaker19]

You don't state the year or engine code. I assume that you have a single coil assembly for all 4 cylinders.

The misfire codes come from the knock sensors. One of them could be bad. Try swapping them and see if the misfire moves to another cylinder. If so, probably a knock sensor is bad.

Thanks, I will try that.

It's 99 beetle GL, 2.0 Automatic, 1 coil for all 4 cylinders with the ignition modual on top of it.

 

[what have i done]

You don't state the year or engine code. I assume that you have a single coil assembly for all 4 cylinders.

The misfire codes come from the knock sensors. One of them could be bad. Try swapping them and see if the misfire moves to another cylinder. If so, probably a knock sensor is bad.

great advice red.