99 2.4L misfire

i am having a misfire on cylinder 1. i have been using injector cleaner and it doesnt seem to be helping. there is a small oil leak around the cam covers and the oil gets down around the spark plug. im thinking that it may have caused a weak spark. u can only notice the misfire when idling at a stop as the engine shakes but giving it a little gas, the shaking stops. the spark plugs are fairly new. '99 2.4L

Thanks, Ben

Might try fixing the oil leak then you might replace the plugs boots and see if that helps.

If that doesnt take care of it then you might consider replacing the coils or the ICM .

i changed the coils around and the misfire didnt move cylinders so im going to replace the coil housing and see if that fixes the problem. How are the cylinders layed out? is cylinder #1 on the right by the power steering pump or is #4?

cylinders are 1234 starting from the pass side.

spark plugs and coil housing have been changed and still no change. i am also getting P0420 code. do i need to change the cat?

The misfire you are experiencing can cause issues with the cat efficiency. Try to eliminate the misfire first then clear the code and see what happens. Also, as to the problem with the misfire, try replacing the boots that surround the plugs. They can be bad and not actually show any issues. Also if that doesn't help you may have to change the ignition module to correct the issue.

ok thanks. ill try to go do that in the morning. should take igntion control module into autozone and have them scan it too to hopefully rule that out

Yes! If they can test it that would help to determine if the module is good. If it proves to be bad replacing it should eliminate the misfire. Also, did you do a compression test on the car. If you have low compression on a cylinder that can contribute to your problem.

well both autozone and advance couldnt test the module so i just got the boots. it still seems there is a misfire so ill take it to autozone tomorrow and get computer scanned to see for sure.

update. car is fixed. the o-rings on the fuel injectors were bad and not seated properly letting to much air into engine.