Marvelicious

Anyone have any experience with these Accel coils?

I just purchased a tC, and I no more got it home than I started getting misfires. My scanner shows that #1 is missing constantly and #2 is almost as bad. I swapped the coils 1 for 4 and 2 for 3, and lo and behold it moved to #3 and #4. I contacted the previous owner who said he'd had problems and replaced two of them with junkyard coils. I'm not sure whether his replacements failed or the other two originals, but my plan is for 4 brand new coils. I'll keep the 2 that still function as spares.

I know, "just get OEM". I might, but since the OEM stuff failed at only 65,000, I'm less than impressed. I'm not going to go out and buy the 4 for $50 eBay junk, but I've had good luck with Accel in the past, and the price is fairly close to what you can find for Denso. Just curious if anyone else had tried them.

Basebllstar

My coils work fine at 110k miles, as are many other tCs. OEM is rarely not the way to go.

Also, you seem to want quality and price. Not much stuff works that way.

But, yes, Accel is a good brand. I believe they make racing coil packs. I would imagine they'd work just fine for you.

Marvelicious

Who doesn't? Thanks for the life lesson... though I had pieced that one together at some point (probably around the time you were born - no offense intended). Let me share a corollary to this: there is little to be gained from blindly throwing money at a problem... hence the question. Honestly, I'm not trying to be an _______, so don't read my reply that way. I do appreciate the response, but it doesn't really help much.

Yes, there are plenty of these rigs that have gone further than mine without coil failure, but I've also found a disturbingly high rate of premature failure, not just on the tC, but on every vehicle running a 2AZ motor.

Actually, a bit of time on Google yesterday showed me a fairly high failure rate on a lot of inline motors with COPs. I've got a theory brewing that the core of the problem is heat. Electronics don't like excessive heat, whether it is a game console or auto coils. Meanwhile, in the inline motor configuration you have the coil sitting directly on top of the motor, generally in a small engine bay and to top it off, many of them (including the 2AZ) have this plastic insulated cover holding the heat right there where the coils live. It would be difficult to quantify but if you could, I'll bet you'd also find more failures in vehicles that spend more time sitting at an idle after driving. I'm thinking about painting the valve cover with some of that insulating ceramic based paint and ditching the plastic cover.

Realistically, I probably won't own the vehicle for another 65,000, so new coils should last until I sell it whether I go for the Accel or Denso (OEM).

Basebllstar

Fair enough. Remember, the majority of people (mostly kids) posting on this forum have no idea what they are doing. That's fine, I'm all for learning, I was like that several years ago when I first started. However, if people aren't interested in helping themselves and researching some before posting, I have an immediate dislike for them. My apologies for the sarcasm, you seem to have done your homework and/or at least have some experience with this.

Heat likely isn't the cause here. Coil Packs are fancy transformers that step the 12V a car generates into a 20,000-30,000 V potential that will Arc across the sparkplug gap. I wouldn't be surprised if the Coil Pack itself generates a high temperature. Also, since all that's in the coil pack is two windings of copper wire, there isn't much to fail due to heat. Similar to sparkplugs wearing, that's just what happens to these coil packs.

My honest guess? The exponential cost increase involved in extending lifespan wouldn't be feasible. 65,000-150,000k miles is probably good enough for them for use in what are supposed to be economy cars.

This is the root question here. and you can't go wrong with either Accel or Denso. So you may as well go the cheaper route (which isn't cheap at all compared to other options).

Marvelicious

No offense taken, it's hardly a stretch to assume someone who just bought a used "youth market" car is fairly young. I picked it up because my commute has gotten longer and I'm sick up putting too many miles on my Tundra. I've owned both a Camry and a Corolla in the past, but the tC seemed like more fun and I don't really need a back seat, but the extra cargo room will be handy. I've owned a fair number of cars over the years, half of them Toyota products, and I generally do my own maintenance. I'm no master tech, but I'm a fairly competent mechanic.

Accel wound up being about $2 apiece cheaper, and more importantly, the shipping estimate said they'd be here sooner, so I went that way. I mostly asked about them in the first place because I ran across several threads on various forums (Scion, Camry, Rav...) in the vein of "I just replaced my coils x,000 miles ago and they're shot again!" I imagine most of those could be traced to buying the cheapest thing the local parts store had on the shelf.

Even though there isn't much to a coil, heat is definitely a factor in coil failures in general - yes they do generate their own heat, and the main reason for dwell control is to keep the coil from overheating. Whether or not the extra heat from the engine is going to significantly influence that is just speculation on my part, but I've got a couple days before my parts show up, so I may get inspired and paint that valve cover. Probably unnecessary, but it's in my nature to try to improve things.

Basebllstar

Well. Now that we have that sorted out. Stick around and pass on your experience. There are plenty here that will listen.

Also, I generally try not to put much stock into threads concerning problems people have. The one person who has an issue definitely will come online and post about it, but of the countless others that did the same thing without issue, how many of them will come online to report it. There's some theory in statistics about this.

Marvelicious

Yeah, you always have to take things online with a grain of salt. Back in the early days of the net I ran across a fairly professional looking webpage (for those days) that was dedicated to letting people know what pieces of ____ Toyotas are. It revolved around the rash of head-gasket failures in the old 3.0 V6, which was a serious problem that could have been handled better than it was, but they tried to turn it into an idictment of the entire brand. I don't remember the exact details (I think they had already replaced the head-gasket once, and the repair failed), but it seemed fairly obvious that the site's owner was attempting to blackmail Toyota into paying for engine work by trashing them on his webpage.

That said, if you search for coil failures on all these motors, you'll notice enough complaints that it can hardly be entirely a coincidence. Ignoring all others, and assuming the PO was honest with me (*cough*) you've got 4 failed coils just on my motor. That speaks to either a common problem or a run of bad parts. Realistically, I think part of the problem is that individual coil packs just aren't as robust a system as the old massive single coil. More efficient? Probably. Better at high RPM's? Almost certainly, but not as tough. It's partially Toyota's own fault - before they (and a few others) changed the industry, a car with 100,000 miles was considered worn out!

I don't imagine I'll become a day-to-day member on here (I don't often have this kind of time anymore) but I'll definitely update this thread with my results and any future troubles (if any). I've got a couple other things I may contribute as time permits as well. I'm planning to do a shift kit on the auto and time permitting that will get a brief write up. It might be nice for those with autos to know that if they want sharper shifts there are options other than the standard first response: "trade in your auto for a manual".

Marvelicious

Well, hardly a long term report, but the Accel coils finally arrived yesterday. They look to be good quality pieces more or less identical to stock other than the yellow plastic and Accel stickers. Fired up like a charm, 0 misfires reported by the ecu via Torque.

I did paint my valve cover. I'm running without the plastic cover and will probably keep it that way.

Marvelicious

I noticed a couple of misses over the last few days, then last night #1 dropped out entirely. Swapped 1 for 4 and the problem traveled with that coil. Swapped in one of the old ones (like an idiot I forgot to label the take-offs, but apparently I got it right) and it's back to functionality.

So, are the Accel coils junk, or does my car kill coils? Getting frustrating... whether it's this vehicle, or poor quality control on the coils, I have people who rely on me to show up when I say I will. I shouldn't have to pack around spare ignition coils like a set of points in the old days...