I actually did try that a while back. This issue has been on going since August. I’ve spent so much on this. This is horrible.
A code for a misfire doesn’t necessarily imply the coil is the problem. Misfires are usually diagnosed by using a pro-level scan tool in conjunction w/ swapping parts around to see if misfire follows the parts swap to the other cylinder. Possibilities for parts swapping experiments include coils, spark plugs, and fuel injectors. For example if the coils on 2 and 3 were swapped, and misfire moved to 3, pretty good evidence problem is faulty coil. On the other hand, if misfire stayed at 2, very unlikely the coil is faulty. Could still be coil (ignition) related, eg a fault w/ the wiring harness going to the coil.
One common problem with coils btw is they overheat b/c they aren’t mounted correctly. The mounting method is what dissipates the heat. Usually happens when coils are replaced incorrectly. Symptom might be car works well until engine warms up. Or symptom worse in hot weather.
Misfires can be caused by internal engine faults too, valve problems, timing chain/belt problems, cylinder compression problems. Uncommon if routine maintenance has been done on time consistently, engine hasn’t run low on oil or coolant. Still, engine mechanicals may need to eventually be considered.
The def’n of a misfire is that the crankshaft fails to accelerate like it should following a spark event. The computer knows the crankshaft angle (of rotation) and when the spark is programmed to occur, so can easily detect when crankshaft fails to accelerate. It can sometimes make a mistake about which cylinder is causing the misfire though. Misfires are most commonly caused by no (or weak) spark, fuel, or compression. After that, probably an improperly timed spark next in line for the most common cause. Seems complicated, but pro-level scan tools (often referred to as “tech-2”) used by someone who knows how use them can usually get to the bottom of misfires pretty quickly.
After-market (parts store) parts failing right out of the box, or soon after they are installed, not an uncommon problem reported here. If coil failure is again the diagnosis, the advice to install an oem coil from a dealership makes a lot of sense.
Thanks so much. I’m going to stop by a repair shop tomorrow. I did have the timing belt replaced. I had the wires done. I had the plugs done and 4x replaced the coils. So much money. Now I’m back to square one. If cars weren’t so expensive right now, I’d buy one and forgo this repair. Thanks again.
I have an update. I went to the repair shop. The guy said my #2 plug was loose. I pray this is the end of this problem once and for all. Thank you all for getting through a nerve wracking weekend lol
1 Like
Please tell us he checked all 4 spark plugs… lol
EDIT: 6 plugs… oops
1 Like
hmmm … seems hard to believe that would cause a coil failure. Maybe the coils that were replaced were actually ok. Coil failure can be cause by the spark plugs if the gap is too wide. The computer will detect the gap being too large, & increase the voltage so the spark can still make it across, but this increase in voltage can overheat the coils. I suppose it is possible the computer might think the gap was too wide if the plug wasn’t making a good ground to the cylinder head. But it would have to be pretty loose for that to happen, usually would produce a very noticeable clicking or popping sound. It’s also pretty unusual to have an undetected loose spark plug with all the coil replacements that have been done. I have a feeling this problem isn’t yet fully resolved.
I don’t think so since it was quick and since #2 had the misfire. I guess he just did that one. I’m going to call tomorrow and see if they can check the others to be sure. I was glad they helped me right away. I actually have 6 plugs. I imagine some are not as easy to get to. I will pay whatever it is to have it checked to be sure.
1 Like