Anyone keep a spare coil + torx driver in their car?

Might be a good idea, I have had 3 fail so far (110k miles NA).
Luckily mine have all failed near home. Car is driveable with bad coil but barely and i assume a long drive could wreck the catalytic.
If it failed on a long trip could ruin your trip even though its a trivial repair.
I was surprised to see my local Autozone has at least 3 brands in stock, I guess I should not be surprised.

I assume the fail rate is so high because coil is inside the head, when I take them out of a hot engine I cant hold them.

 

When I had one go bad, I replaced all 4 and kept one of the old ones in my tool bag in the trunk. I don't want to be on my Ohio to Wisconsin drive and have one go out.

I also have my old diverter valve in there as well. It wasn't bad but the old style. I have a can of green slime tire repair, a tire plug kit, 12v compressor and a toy spare tire back there. I have worked sales since 1997 and do not like being stuck on the road side.

 

All ignition coils of the COP (Coil on plug) design get hot; it's normal. And no, a failed coil won't cause a problem for your catalytic converter because the DME will sense the misfire and shut down the fuel injector for that cylinder.

Also, stick with a name brand ignition coil (or OEM supplier)

The OEM supplier is Eldor; make sure you avoid Amazonian ignition coils.

 

^^^^ YES. Completely agree with advice to stick with a know brand. I've personally used Delphi with good results.

 

Slightly off topic but still relevant. With 134k on the odo and an unknown maintenance history (seems in good condition so far), is it advisable to go ahead and do a coil replacement if you're intending to swap the plugs this winter? Or just ride it out until you have a coil failure? Just curious what folks do or what is advisable. This on a NA car.

 

A PF (probability of failure) curve for ignition coils doesn't exist. Some will recommend changing them at 100,000 miles, but you could have a new coil fail at 10,000 miles or it might last 200,000 miles or more. In my opinion, run them to failure.

Now if your have an S model, and have modded it, that's a different story since increased combustion chamber pressures require more powerful coils and typically a change in spark plugs and spark plug gap.

 

I agree with mkov608.

However, at around 140K miles on a whim I had new coils (and plugs) installed in my 996 Turbo. The engine was running ok. No signs of any issues. Just on a whim. Well, that and at 132K miles I had new O2 sensors installed -- one was triggering a code that pointed to the sensor heating circuit but the engine was not manifesting any signs of any issues -- and after the engine ran better. Which kind of surprised me.

So new coils and new plugs were installed at my request. Check that. I had just asked for new coils. But tech said while he was there... I agreed and gave him the ok to replace the plugs. They had about 10K miles of service left but the exhaust system has to be dropped to change the coils and plugs so it made sense (and cents) to change the plugs at the same time.

After to my surprise the engine ran better. Had had the plugs changed before on miles and the engine never perked up so I attribute the running better to the new coils.

The flip side is I drove several cars to 150K and beyond, one to 317K miles, and never replaced a coil.

So if it were my car I could live with the coils or replace them. If they are not super expensive and you can replace them yourself, when you do the plugs replacing the coils at the same time -- and the O2 sensors, too -- might not be a waste of money. With a used car you get those items renewed and then barring the rare early failure probably never have to touch them again. Well, the coils at least. Plugs and even O2 sensors might need replacement if you keep the car long enough. Drive it enough.

If you go with new coils and O2 sensors buy good ones. I've always gone with factory plugs, coils and O2 sensors.

If you replace the coils handle any coil wiring with care and be sure each coil is secure on its plug and each coil is securely connected to its harness connector. And if there are coil grounds they are in good shape too.

 

This makes perfect logic ! If in there, why not replace - not very expensive ( except the O2 sensors - they might be, I am not sure ). There are times when you don't replace unless it is broken, but don't think this is one of those.

Your story on your 996 brings back memories of my 997. I bought it with 35K miles ( turbo with the metzinger engine ). I was having some wallowing with the clutch coming out of first, so bit the bullet and upgraded with Sachs clutch and GT2 pressure plate. After dropping the engine ( a necessary evil for clutch replacement ) - I did everything else that could be done while the engine was out ( I almost pinned the cooling lines, but ended up just resealing ). Upon inspection - we felt they were the original plugs and never changed ( this is an 4 - 8 hour job without dropping the engine, but only the cost of parts when it is dropped ). Porsches are a pain - so preventative maintenance is key.