Interesting. Look at the plug gap difference between the new one and the old ones. Is that supposed to be equivalent? Because the new one has a little nublick on the ground strap and that gap looks much smaller than the others that do not have that protrusion. Have you measured them and can confirm this is an effect of the picture or is real?
That was my picture, unrelated, sorry, it should be deleted now.
Oops sorry. Wasn’t paying close enough attention!
Did it set off a cel?
It’s possible one of the new coils went south. A shop with the Toyota scan tool can test the coils for you. You might could do a spark test yourself using a spare spark plug, one cylinder at a time too. Other problems can cause that symptom of course. A vacuum leak or exhaust system leak for example. Ask your shop to measure the intake manifold vacuum at warm idle. Another idea: Suggest to read out the diagnostic codes. The CEL may not have come on — yet. But there could still be diagnostic codes stored as pending. That would give you some more clues.
Remember that professional mechanics deal with the kind of problem every day. They’ll often have seen it before, recognize it immediately from a test d rive, and know exactly what the problem is. It will probably pay off in spades to have the diagnosis done professionally. Then you can decide if you want to fix it yourself if you want.
Yes. Both times.
i cant believe all 4 original coils went bad at once. too bad you didnt save them. 3 of them are probably good. you could use them as backup for the knockoff coils you bought
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I’ve still got two originals that are still good. One went bad then another so I figured I’d do them all at once. I don’t think it’s the coils at this point because of the lack of a code. Could a fuel pump issue lack a code?
that would make for a nice logical problem … “you have two groups of 4 gold coins, but you know that at least one coin in each group is counterfeit, how do you find 4 coins which are good?” 
A fuel pump being problematic usually rears its head when you’re accelerating, going up hill, etc. I eliminated that as a likely culprit when you said it accelerates fine. I’m convinced it’s not fuel or ignition related.
Actually in the past 24 hours I’ve noticed a slight bucking in the beginning of acceleration. It may have always been there but now seems quite apparent.
It ended up being the catalytic converter. Appreciate all the input guys! Thank you
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Glad your Corolla has returned to a smooth runner. Good for you
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Sincere thanks for taking the time to post back. We learn from the feedback, and yours will become part of the database that we use to help others.
Happy motoring.
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has anyone on here used a coil from Isa auto parts, just ordered one from Walmart.q
Does it really matter? You already bought it, from WalMart of all places. Not really known for quality auto parts. Remember in most cases you get what you pay for. Good luck.
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