I haven't noticed that issue with mine. I've had mine for several years now and both of them appear to output the same light as before.
Reach out to the vendor. They should do something about it. Hopefully they send you the second generation kit which is supposed to be brighter.
Are you kidding? The understeer on the stock suspension is horrible.
I got the TRD rear sway bar and that alone made a huge difference. Car has a very slight oversteer with it and it made cornering a lot better
Like others said, get the codes. There are literally tens of thousands of reasons why a check engine light can come on and without the code, there isn't much to say.
No! Rears are always different from the front. Rear discs are typically solid with no venting vanes in-between the plates. The fronts also have a larger diameter.
If you are doing the rear brakes, you'll want a rear-caliper tool that locks in a 1/4" or 3/8" ratchet. Remove the rear...
Exhaust drone doesn't bother me, but it does get loud when going up a hill, otherwise it's there but subtle.
As far as Bluetooth, exhaust wouldn't ever interfere with it.
I did it myself. It wasn't bad but sliding the rubber grommets off the old exhaust requires a liberal amount of soap water and elbow grease. I thought the rear sway bar would take longer but that was a 5 minute job. Exhaust I fought on it for an hour.
I bought it at Toyota of Escondido for MSRP...
Throttle Body Spacers don't really do anything. More of a gimmick than a true power adder, unless of course that throttle body spacer has ports for nitrous injection ... then you might be on to something.
I change every 10,000 miles. Why waste the money unless you live in regions hit with cold?
If you go 10,000 miles, make sure whatever filter you buy can handle it. Lots of filters out there only rated for 5,000 miles.
There's a button in the glove box to reset the TPMS.
After the car has sat for 3 hours or more, turn the car on (without starting it) while holding the TPMS button. It blinks 3 times when calibrating. Wait another minute before starting the car or turning it off. That's it.