What are some symptoms of bad coils?

[Herblenny]

I replaced all my coils and wires today.

I have to say, it was quite easy to replace. Took me about 30 mins to replace all and without really taking ton of shit off. I was dreading that I might have to take my AutoEXE strut brace but didn't have to..

New coils were pretty cheap.. I thought I'll be spending 100+ each but all 4 were in 100 range (under 130 for all). Since I didnt have time to order upgraded wires, I just got the Mazda OEM ones for under 60.

With long 10mm socket, I took each coil and wires off and replaced them from rear to front. Again... total of about 30 mins.

After installing the new coils, started up (cranked better but idles hunted a little), and went for a drive.

I got the car warmed up, took it on an interstate... tried to hit red line in 4th gear and when i hit 6.5K, it cut off... I shift up and I was able to keep pulling the car.

I filled up the tank and got back on the interstate and in 3rd, I was able to hit red line without an issue and it was nice and smooth!

I shift up and hit 7-8k in 4th with out any issues.

So, I think all is well with the new coils and wires.. Next test will be the drive from Bham to the DGRR.