Hi all,

My C4Cab started sputtering yesterday and the engine light came on. I took it to my local garage and they determined it to be the ignition coils & spark plugs. My car is a '01 (of which I owned it only since '04) and it's clocked just over 73,000 km.

I've opted to go for Design911uk's Ace branded ignition coils & Beru spark plugs.

The questions I have are :-

1) how long before ignition coils & spark plugs give in? Is 73K km a decent life out of it?
2) Any opinions of the Ace branded ignition coils?
3) I just ordered the two aforementioned items. Do I need anything else? O-rings, etc?

TIA

 

Spark plugs should last 48K.

 

IIRC, if you have the platinum 4 prong NGK, they are rated over 100k.

Get factory Beru coils, Bosch or NGK plugs(prefer NGKs), Spark plug tubes and o-rings.

At that mileage, the spark plug tubes and/or o-rings could become brittle and crack. Make sure to get factory tubes/rings or you'll have to replace them sooner next time due to inferior materials on the aftermarket ones.

 

Thx for the responses. So with 73k km, it looks that I have had a decent life out of the spark plugs.

Unfortunately I've already ordered the Arc branded ignition coil set & design911uk just shipped it out. I'd guess I'd see how long of a life I'll get out of these.

Your respective advices are truly appreciated.

 

My coils lasted about 112000 km at which point I started getting misfire codes thrown. I suspect the spark was weak before that but not bad enough to throw a code.

 

Fwiw, the coil windings can last practically forever if the rest of your electrical system is working properly. It's usually the plastic housings that get brittle from the constant heat and allow the current to short to ground. Some have just RTV siliconed the cracks in the housings and ran another 100k just fine.

 

That makes sense Alpine. The weather out here (Northern California) is very mild (not too hot or cold) and the car was always kept in a garage so the plastic on the coils probably lasted a bit longer than most.

After I put in new coils (and plugs) the engine ran MUCH smoother.

 

You will need to buy a boat plug to remove the sleeves. (Take a new sleeve to the boat place for best sizing the rubber plug).. Tighten it in and bend it to one side so it grips better onto the inside of the sleeve. You might want to remove the mufflers in the wheel wells for easier access or you will be working by feel alone on 4 of the plugs. Good luck.

 

Thank you all for your advice here. My ignition coils & sparkplugs were replaced and it's running much more smoothly than even before I started to have the engine light & sputtering symptoms.

In fact I've not felt my car run so smoothly in years which leads me to ponder on a question. At what point does the the car start to exhibit the engine light & sputtering symptoms? Would, say, a failure ignition coil/sparkplug show or would it be a few?

The reason for my question is that my poor car mileage and sluggish pickups have been around for some time and I'm wondering if I've actually been having these ignition/misfiring problems in a while but the obvious symptoms only started to exhibit when more and more of the ignition coils and/or the sparkplugs start to fail.

I feel it's almost running too smoothly that I speculate the engine is running more efficiently, therefore improved mileage.

 

Efficient ignition = full combustion= more power= less throttle= more complete burn = smoother engine= more mpg

If coils are leaking, their not running at their peak just like if your electrodes are worn, the gap is inconsistent and tips corroded to be less conducive as well. It can be a combo of these over time. The multi-electrode plugs do help from a longevity perspective.

 

Yes I'm aware of that. The point I was trying to make was that I was experiencing poor mileage & "less than smooth" rides before the more obvious symptoms of the engine error light & engine sputtering.

And therefore the question; Does that mean that I was having ignition coil, or spark plug misfiring one-by-one and gradually lead to the engine error light & sputtering. How many spark plugs have to fail before the error lamp lights up & sputtering to exhibit?

 

There is no answer to your question. They last - as long as they last. Depending on several factors such as temperatures where you are, gas used, driving style..... your plugs are scheduled to be replaced per the maintenance schedule - stick to that unless there is an issue. The coils last until they crack and/or go bad. When they do, replace them. Your dealer can tell you when that happens as they should be checking them each time you go in for service. Mine were replaced around 60,000 as two showed issues so they did all under warranty.

 

Coils and spark plugs do not just go dead but rather deteriorate over time/use, therefore do not trigger the cel.

As an example, my coils were cracked for about 10k before I decided to replace them. During that time my cel light only came on twice and only during wet conditions. The idle wasn't silky smooth and I wasn't even sure if I was doing complete burn at times. The point here is you really need to do a visual inspection and not totally rely on the cel light as the tolerance to trigger for any ignition symptoms is on the loose side.

 

Thanks alpine003. Cheers. That does make sense & answers my curiosity. Now that you're mentioning idle wasn't smooth, I do recall experiencing the same thing too occasionally a few months. So I guess the problem started further back but I didn't recognize the symptoms.