Rough idle?

This can be a vacuum leak which I would test when the engine is cold only. here is a guide to help you also have you installed new spark plugs and coils. That is a problem with these cars, here is how to change them out as well:

https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge

Spark Plug Type:
DENSO .................... SK20R11
NGK .................... IFR6A11

Spark Plug Gap New - mm (in.): .................... 1.0 - 1.3 (0.039 - 0.051)
Torque: .................... 18 N.m (178 kgf.cm, 13 ft.lb)

This guide will help walk you through the replacement:

https://www.2carpros.com/articles/how-to-change-spark-plugs

Please go over these guides and report back.

I believe my 2006 Toyota corolla takes sk16r11 and not sk20r11 that you suggest. Could you double check that? Thanks, Robert

Hi Robert,

I show 1.8 liter engines for this car can you please confirm the engine size?

Yes, 1.8 liter.

There are two different 1.8 liter engines here is the spark plugs for this option, L4-1.8L (1ZZ-FE)

Spark Plug Type:
DENSO .................... SK16R11
NGK .................... IFR5A11

Spark Plug Gap New - mm (in.): .................... 1.0 - 1.3 (0.039 - 0.051)

Torque: .................... 25 N.m (255 kgf.cm, 18 ft.lb)

Please let us know what happens.