I have 2004 TL Automatic with 230K miles on it. Yesterday my son was driving it and it started to "rumble and shake." He got it home and I read the codes from it. I had P0303, P0305, P0306 for misfires on cylinders 3, 5, and 6. And I had the generic P0300 for multiple misfires.

I took the forum advice and replaced one (cyl. 5 since it was the easiest) and took it for a ride. Still had the miss. Came back and read the new codes. 5 was fixed but 3 and 6 were still reporting misses. Since replacing cyl 5 made that one work, I went and got two more coil packs and replaced 6 and 3. Took it for a ride, ran smoothly and no more codes. Looks like it is fixed. Easy fix...

But, my question to you is this... Can anybody think of why I would lose three of them all at once? Geographically they are all in the same end of the engine. I didn't see anything obvious that may have caused this to happen. I'm hoping there isn't another problem in there that blew these out and will do the same to the new ones again within a short period of time. All insights are welcome!

 

A few comments:

• With these engines, when one coil pack fails, multiple misfires are recorded.
• With two bad coil packs it is very difficult for these engines to idle, and depending upon which two, almost impossible.
• With three bad coil packs, I rather doubt the engine would have run at all.
• My bet is you only had one bad coil pack and it wasn't #5.

 

Honda Coil Packs, are of good quality, and normally, don't fail. Experiencing one coil pack failure, while not rare, happens, with some frequency. Experiencing three failures, in a fairly short time period, would be very, very rare. Unless, a coil pack is mishandled, as in dropped, or kicked around, they normally, do not fail. I agree with horseshoez, most likely, only one coil, was actually bad!

 

Thanks for the feedback. In hindsight I probably should have kept swapping coil packs until I swapped all three before buying two more. With my 20% off coupons for Advanced Auto they didn't cost that much and it is possible that they may fail in the future since they aren't genuine Honda/Acura. It looks like I might have 2 spares if there is another failure...

 

Yeah, two out of your three old coils are probably still good; the question is, which one is bad?

 

When I have some time, I can swap them back into the car and see which one causes the problem again...