My son has a 2009 Corolla. We replaced 2 coils over the years, based on misfire codes. Plugs replaced also. Last year we got another misfire and replaced all 4 coils. So far no codes, no misfire symptoms. Toytota’s are fussy about spark plugs. Only use Denso, not an equivalent. I could not find the plugs @ my local parts store, but got them from the dealer, the price was in line with McPart store prices.
No stats, just my humble opinion.
1 Like
So you’re comments are worthless.
3 Likes
One mechanic told me to use only OEM Toyota parts. My mechanic had been using parts store coils/ wires. Any thoughts on this?
OEM Toyota coil packs are made by Denso or NGK. For most Japanese designed vehicles I’ve always used either Denso or NGK plugs. You do NOT have to buy them from the dealer. The only difference is the plugs and coils will have the name Toyota on them and cost twice as much.
Depends, doesn’t it? While I can’t cite hard stats my opinion is based on experience sand that of other Toyota owners with whom I’ve spoken and owners who have posted about the issue here in this community, plus conversations with our regular mechanic and our daughter’s boyfriend, who is a mechanic at a Ford dealership. Nevada_545 and SteveCBT both mentioned coil failures on Toyotas in this thread. So either I’ve had bad luck, along with a number of other owners, or you’ve been very lucky. You can dismiss my opinion if you choose but that doesn’t make it “worthless.” Oh, and if you think my comments are “snide” you haven’t been paying attention.
1 Like
WRONG…You were NOT stating YOUR opinion. You were making a statement as if it were a FACT. There’s a HUGE difference. Your opinions are NOT facts unless you can back it up with data. Your snide remark about my experience as being lucky…that was completely dismissive.
2 Likes
This is the service bulletin for the failing ignition coils in 2004 Toyota vehicles;
This is the service bulletin for the failing ignition coils in 2008-2010 Toyota vehicles;
T-SB-0047-10 Toyota Technical Service Bulletin (tsbsearch.com)
Thanks. If I’m reading that correctly, that’s for v6, it’s in 4cyl
Ours is a 4 cylinder
I assumed that you have a 4 cylinder engine since you stated that the timing chain has been replaced. The reason I posted those links is because this “coil” discussion inspired an argument.
Like the dealer, we have “no clue”, you have not provided any details, 5 days later and your car has the 4 cylinder engine. I wonder if your misfire problem is really due to coil failure, you have not posted the fault codes.
What kind of parts is that mechanic using? The dealer is using OEM parts, are those failing?
Fault codes are F301,302,303,304. Mechanic using after market and suggested using OEM next time coil fails. After a week at the dealership, they found no problems. If any coils fail again I will use OEM parts and change myself. Dealership drove car and tried to recreate the problem which did not happen and without a fault code they said there is nothing else they can do. They have no additional ideas as to cause and were once again a waste of my time.
You were asked earlier about whether or not the spark plugs were changed. Were they? Plugs should be when coil packs are involved.
With plugs out a compression check should be done. Your car is 17 years old with an unspecified number of miles. If compression is dropping misfires can develop…
My philosophy is always make sure the patient is not terminal first before administering any parts. Think Advanced DIrective…
3 Likes
Based on what I know–not what I’ve guessed–based on experience and research, you are in fact fortunate that you haven’t experienced a coil failure. The fact that I can’t quantify the odds in a way that’s satisfactory to you doesn’t change that. Anecdotal evidence still means something.
As for being “dismissive,” do you mean what you’re doing to me? Characterizing someone’s lived experience as “opinion” is pretty much the definition of dismissive. Think carefully, reread my posts, and I think you’ll realize I didn’t say you were lying or ignorant. I didn’t dismiss your own experience as “opinion.” I didn’t demand “proof.” I simply said your experience doesn’t jibe with what I know to be true and I believe you’ve been comparatively lucky–in fact more lucky than that–and I stand by that assertion.
If a dozen people eat tainted meatloaf at the local diner and only six of them get sick that doesn’t entitle them to say there was nothing wrong with the meatloaf. It means they were lucky. If someone owns a vehicle with a reputation for coil failures–or even several such vehicles–and no coils fail that doesn’t mean there’s no underlying problem. It means the owner is lucky.
In any event, I’m done. Among other things, the forum software is nagging me about replying too many times to the same person. If you choose to interpret that as some version of “I give up” that’s your privilege.
2 Likes
Then it’s just an OPINION. NOT a FACT.
I was being dismissive to you because you were being dismissive to me. If you weren’t dismissive to me then I never would be dismissive to you. You want respect in this forum…then give respect. You don’t.
1 Like
Hm. I’ve owned something like 16 vehicles from various manufacturers over the years, drove them over a million miles total, and had zero coil failures. I guess I should start buying lottery tickets.
Plugs were changed, compression is good.
Is it not ECM/ECU who actuates the coils?
I would entertain the idea of ECM/ECU final drivers could go bad and lead to coil failures.
I’ve seen a number of “we will test/repaid your own ECU” advertised on eBay for example, with quite reasonable terms.
Another potential issue would be ECM/ECU getting “bad ground” or engine itself having grounding issues.
In my opinion, coil failures aren’t super common
certain engines seem to be more prone to have this problem, though
1 Like
That I’ll agree with, Maybe some Toyota engines are that way. I haven’t run across them yet so I won’t say it’ll never happen.