Hi guys! Sorry for the long post. Hope you can help me. I haven’t used the car in a month. I keep on getting a P2300 code: “Ignition coil A primary control circuit low”

I tried to troubleshoot by switching (in different positions) the spark plugs and the ignition coils, but I kept on getting the same error code (with misfire) even when I reset it, which made me think that neither is the problem. When I did this, I noticed that 3 of the 4 spark plugs were wet with oil (valve cover leak), with the spark plug in cylinder 1 being in the worst condition. It wasn’t too much oil, but it had entered the inner part of the ignition coil boot that covers/meets the spark plug.

I have since replaced the spark plugs, valve cover gasket/s, and cleaned the boots of the ignition coils from oil. (The spring part of the coils that meet the spark plugs were dry). The car worked properly for some time, but after 10 minutes, suddenly had a misfire and threw the same p2300 code. Check engine light is intermittent (comes out 1 out of 5 times, maybe).

I tried to do some research but couldn’t get too much info. I did notice that the code means that there is a “possible ground to the engine”. I don’t know what it means in this context. Is there an easy trick/ way of troubleshooting or checking this?

I then cleaned all of the wire contacts of the plugs going into the ignition coils and tightened the female contacts a bit to ensure that they fit the ignition coils snugly, to eliminate the possibility of causing the error from a loose connection. I thought I had fixed the problem. I drove the car and left it running for a total of at least 30 minutes with no problems. I switched the engine off and let it rest for maybe an hour or two. Then, when I tried to start it, it threw the same error again (with misfire). This is really frustrating and I hope someone can help me.

Observations:
1. I think the misfire happens more/easily when the engine is hot.
2. The misfire doesn’t happen immediately. When the engine is cold, it could misfire after a few minutes or maybe a few seconds after starting the engine. When the engine is hot, the misfire happens around 5 seconds after staring the engine. It feels like the car sees the problem somewhere and then reacts by shutting of the fuel/electricity going into the affected cylinder. (Same cylinder/code everytime, even when switching the positions of the plugs and coils).

Is it possible that the problem is in the wires going to the coils? Is there a way to check this? I don’t want to spend unnecessarily on new coils if they are not the problem.

Help please! Thank you very much.

 

From the code and the description of your diagnostic actions it looks like the problem is with the wiring to the coils. The code does not indicate a specific cylinder and when you move the ignition coils and spark plugs to different locations the message doesn't change as you would expect for an issue with a particular coil. Check the wiring to the coils.

 

Yeah, I agree. That’s what I read in one of the articles I found for this code, but I honestly just don’t know how to go about checking the wiring of the coils. I mean, visually, they look ok. No chafing on the wires, the plugs are all intact - not brittle. How/where do I start? Is the damage in the portion of the wire right at the plug, could it be somewhere in the middle, which of the three wires is it? These are the questions going through my head. Is there a trick or correct way of trouble shooting this because I can’t find anything online?

Can the specific wire/s just for that plug be replaced without having to change the whole set/harness for the other plugs?

Thank you!

 

Posting this for the benefit of others who may have the same experience.

I removed the spark plugs / ignition coils again to do a final cleaning, and to make sure everything’s in order. Remember that I changed the valve cover and spark plug housing gaskets because it started leaking oil into the spark plug chambers. When I put it back before, I only cleaned the spark plug chambers and didn’t bother to clean the screws holding the coils in place.

This time, before I put everything back, I made a visual check on the holes where the screws went, and there it was. They were filled with oil. I then cleaned them out with brake cleaner and some cotton buds. I also cleaned the screws.

I’ve been using the car for a week with no problems.
Hope this helps.

 

Hello! I have the exact same problem and I don't know what else to do. same symptoms and P2300 error. spark plugs and coils are new and fastening screws are clean. could someone give me some help?