I would check that the nuts on the ignition coil are tight and inspect each and every plug. You might have moisture in the plug itself! Theres a small rubber oring inside the plug make sure they are all in there place. Also did you wash the engine after?

Another thing is where did you purchase the spark plugs from? As there have been a lot of counterfeit oem toyota/lexus plugs selling on ebay for a cheap price

 

Use NGK spark plugs

 

I've said it before..
This has been discussed many times.. There is no such thing as "pre-gapped" plugs,, period.. Our plugs fit hundreds of different types of vehicles and applications. Its is impossible for any plug manufacturer to "pre-gap" a spark plug and sell it as such. Additionally, have you seen "pre-gap" on the plug box? I hope we get off this per-gap stuff and learn to gap plugs prior to installing them, sure will save some time.

 

Well actually, a BCPR6ES-8 comes with a .8mm gap whereas a BCPR6ES-11 comes with a 1.1mm gap.
So there absolutely is such a thing as pre-gapped plugs.

 

Fact:
ALL spark plug manufacturer's release their plugs with a standard gap. This is to simply get you started and allow proper gapping. 99% of the issues after eplacing spark plugs are due to improper gap or inconsistent gapping which is a direct affect from lack of experience.

 

Also recheck all the torque on the plugs and make sure the mating surface is clean