SkoorbMax

Some of us have experienced poor ignition coils in our 5th gens. Mine was rattling for at least 20k miles very infrequently and slowly getting worse, but only recently did I finally figure out (ok Nissan told me ) that the "rattling" I was hearing was in fact knocking due to a bad ignition coil. I replaced the set and no more rattling. However, they also told me that if I didn't fix it the rattling wouldn't cause damage.

Still, a couple of links I've found do state that piston damage, among other things, can be caused by this long term. Now, I didn't get it all that often, but sometimes the rattling was pretty bad for 5-10 seconds while I was in a particular gear.

As I understand it in some cases this is caused by the piston slapping the cylinder walls, and it makes sense that this would wear out an engine.

As far as I'm concerned this was caused by faulty ignition coils, but since any damage (if there is any) won't make itself visible until I'm well out of the powertrain warranty, what recourse do I have? Or should I merely not worry about it? Most miles on the car were driven without the rattling and it would only happen while accelerating at certain infrequent times, but nonetheless I'd think that over thousands of miles a small bit of damage would have been caused, right?

spirilis

iTrader: (2)

Yes, excessive (keyword "excessive") pinging, and any major pre-ignition can damage the engine.
I'm not sure how serious the pinging is with bad coils... actually another question I have is, WHY does pinging occur due to bad coils?
why isn't it just ordinary misfire or whatnot...?

SkoorbMax

*shrug* I'm not sure. I just know that there was a serious rattling on occasion, and now that the coils have been replaced the rattling is totally gone!