Just like the title says, can they be? I know its a "noobish" question but what is the lifespan of a coil considering it doesnt throw a CEL?

Spark plug wires wear out. I know the COP system is supposed to have much more longevity, but given heat/time and mileage would they not eventually wear out too?

 

As a service manager at a dealership, the way we define a wear item is something that on every car goes bad at about the same mileage. IMO a coil is not a wear item, although spark plugs would be, just like belts, brake pads/shoes or bulbs. Just my 2 cents....

 

Nothing lasts forever, and with the many parts on a vehicle, given time and mileage I'm certain they would eventually fail. Many times they are misdiagnosed and replaced when the engine is not operating correctly, but normally they will last the duration. No, not considered a wear item.

 

I am thinking along the lines that on spark plug wires the insulation dries out and cracks. While thats not a specific problem on COP systems, I am just curious as if I should put it on a list if items to replace.

I have a power problem, but I dont think its a spark/ignition issue. I think my issue is a broken VIAS in the "high" position.

 

Power problem throughout the entire range, or sporadic?
I would think if a coil would go south, a definite miss would be felt opposed to a power problem. You can always check current to the solenoid to be certain of the VIAS condition. Check the MAF sensor?

 

I have two MAFS (old and new version) and operation is the same. Power just sucks down low (below 2.5K) like I have AC on a 100HP 4 cyl. Honduh. Once it gets about 3.5-4.5 it starts waking up. I am on vacation in two weeks and am pulling the VIAS apart to see what the story is there. I really suspect thats where the problem is. If you have bad O2's, spark, fuel filter your gas mileage doesnt go UP.

 

I would think that if the VIAS is not functioning properly you'd have poor performance at the higher RPM's rather than lower.

 

Wont know for sure until I pop it open. I am under the impression that the cup can break free of the rod in any position. So therefore my assumption is that the rod can be in any position.

Seeing pictures and actually pulling it apart of course are two different things. Also will be checking all the vaccuum hoses and connections to the TB inlet as well.

 

heat is the biggest factor with electronic parts. Things are always longer lasting(except bodies) in colder climates

 

Im not 100% on this but I have been doing A LOT of research on these cars and Im pretty sure the coils had a factory problem. If it hasnt been replaced since the car was new then it might be faulty...

 

Coils normally fail under high load conditions, such as at high rpm where they are discharging very quickly at 40+ times per second etc.

The problem your describing appears to be O2 sensor related, which is the operational range of the O2 sensor in closed loop

 

So you are thinking that its an O2 issue because I have boggy acceleration down low, wakes up up top?

I did replace the lower banks of O2 due to a CEL about 30K/4+ years ago. (PO120).

 

Think about any electrical problem, a weak battery or alternator is often exposed when headlights come on and the interior lights dim or trying to start the car(starter motor) when massive current is required.

So for the coils to be failing, it is odd that they are working fine at high rpm when they are discharging quickly, drawing a lot of current and generating more heat etc. The closed loop O2 system is operative in the exact rpm range you describe, hence why I am speculating that it is O2 sensor related OR in my experience with a few Nissan SR20 engines, one fuel injector is leaking which causes the O2 sensors to try and compensate by pulling timing and reducing fuel on all cylinders to get the O2 sensor back within range. Of course, since the O2 sensor measures the combined exhaust gas of multiple cylinders, if one injector is leaking then the others end up running lean... with retarded timing as a safety buffer.
I would be looking at injectors or O2 sensors

 

COl -

C.O.P = Coil On Plugs???

Interesting diagnosis....glad my car isn't doing that YET.

Col - keep us posted on how the tear-down and analysis turns-out.

gr

 

Yes, COP = Coil On Plug. :-)

I will be checking into the O2's. Need to find a "test procedure". If its an injector, pfft I am not digging into that, Ill cut it loose prior to that. Well, if I still have my job that is.

BTW, I drove it yesterday and it seemed to drive fine. *sigh*