I've had intermittent rattling, which was diagnosed as knocking by Nissan - cause being bad ignition coils in my 2000. I just replaced them this week ($309 for the coils + $90 diagnostic) and the knocking all but dissapeared but then today I was able to find it a little bit again. It's far, far more subtle than in the past and I can hardly ever hear it (I have new plugs also and only use 93 gas), but is this something others experience, or should there truly be a way to get rid of this annoyance?

 

Bad coil.

Has happened before. Take it back and tell them to figure out which is bad.

If that's not possible, hopefully you kept your old ones to try and use to diagnosis which is bad.

 

Yeah I kept the old ones So, I guess the only way to fix this is to replace them one at a time? It's so freaking subtle that it's really quite difficult to replicate. Since I did the work myself I can't go back to them and have them figure it out, and I think it would take a long time anyway since for the most part the coil works if this is the problem...but then I have to use one of my coils and I'm not sure which of mine are bad. Still, it's a starting point. I'll start doing them one at a time until I can try and find the bad one...

 

Not sure how much this might help you but I had the same problem on my 2003 and after many many visits to mostly incompetent service dept's I finally ran into a tech that knew what he was doing. Having checked the MAF and the possibility of ignition coils(which are supposed to be ok in 2003) they set back the base idle by 2 points. That solved my problems. Maybe that approach could help you as well.

 

I would suspect the MAF as well....

 

I'm guessing none of that would be covered under powertrain? I run out in about 105 miles and it looks like it will be difficult to get the car to nissan before it runs out. I'm going to try switching the coils again (I've done three and confirmed that if it is a bad coil of the new set it's going to be of the rear three), and if that doesn't work I guess keep looking...

 

your injectors could be dirty. Try cleaning it w/B&G product. Mine slight knocking was gone after doing so.

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Thanks for that idea. I'm gonna check to see if it's coils first and confirm it is or is not and then that should make for a good final step. I wonder if that could also be the source of my morning chugging, which is surely because my car is running lean (first few min when the engine is really cold it chugs a bit like a bastard, although some others here have said that theirs have always chugged).

 

Nissan service is