I see sparks emanating from the sides of all six coil packs.
In the process of diagnosing a camshaft sensor error I took the time to look under the car at night with no lights on. What I see is sparks emanating from all six coil packs. From what I can tell the sparks appear to be jumping between the coil and the surrounding metal casement attached to the coil. In an effort to eliminate variables, I replaced all the ground straps to the engine as well as the negative ground to the battery. Additionally I pulled all the coils and plugs. The plugs are platinum plugs with approximately 30,000 miles on them. The wires were replaced at the same time as the plugs. I did notice some corrosion on the coil packs and used a small brass dremel tool to clean up. Additionally I apply dielectric grease and put everything back together. Although the car appears to be running somewhat better, I'm still seeing the same sparks emanating from the coil packs. The question is: has anybody else seen or experienced the same issue? Is this a sign that the coil packs are damaged?
Yes, definitely. Should replace the coil packs. Just make sure the spark is not leaking out the wire to ground.
Is it normal for all 6 to fail?
No, and they may not be not be bad enough to replace. Ordinarily when a miss in a cylinder develops it will set a code in the computer thus setting off the check engine light. Scanning for codes would show like a po303 which is a miss fire code indicating it is at cylinder #3. So then you'd diagnose that cylinder. Electricity of course find the shortest path to ground, so spark plug wires maybe starting to break down, or plugs are getting worn causing a larger gap for the spark to jump or a crack or something with a coil.
No codes for misfire. Only intermittent code for camshaft position sensor. Did an ohm test on each coil and 3 were .9, 2 were 1.0, and 1 was 1.2. The vehicle has a somewhat rough idle... that is to say the idle gives a slight shake. There are no issues with acceleration or power... Of course until we started to have the camshaft position sensor issue. I don't doubt that I have a bad/failing camshaft position sensor, but as I have a obvious issue with the coil packs I am going to attempt to resolve the one issue first and eliminate a variable. I'm going to try replacing the plugs initially to confirm that I do not have a resistance issue with the plugs. The wires and boots were replaced with the previous plugs and show no sign of wear. My gut is telling me that the coil packs are bad… Or in a state of going bad possible because of bad plugs or wires. I have no idea how long this condition has existed, but it could be several years or more. This might account for the fact that all the coil packs appear to be exhibiting the same aforementioned sparking. I was really hoping that somebody would have seen this issue before.
Looking for a Used 300M in your area?
CarGurus has 334 nationwide 300M listings and the tools to find you a great deal.
Search Chrysler 300M Questions
Chrysler 300M Experts