Sparked up

[Lola Zamoi 5]

Hi, can anyone assist with a big PLEASE. My Avensis runs on K16R-U11 plugs. 

However, when I went to replace the spark plugs I found NGK IR IFR6T11 plugs fitted into the cylinder head. I questioned this and was informed that the Iridium plug was a better choice. However, Toyota UK state the Denso K16R-U11 is the only plug suitable.

Iridium plugs are supposed to give a better spark, more power and better MPG.

Is it okay to run this type of plug, the NGK IR IFR6T11 in my car ??? Anyone have the expertise knowledge to help a old sod out please.

[Lola Zamoi 5]

To the above. Correction. I refer to the 2009 Avensis which was sold in 2008, still a 1.8 vvti engine. Added to my fleet of Toyota vehicles

[Konrad C 956]

I checked the Denso catalogue and also the Haynes manual which is fairly accurate, and the Denso K16R-U11 is the recommended spark plug. This spark plug is not Iridium, and is the only 1.8 Avensis engine (1ZZ-FE) that didn't have Iridium as standard! 
Here is the specs from the Denso catalogue - Denso K16R-U11 https://www.denso-am.eu/e-catalogue/

    

The other options are K16TT and the Iridium option IK16TT. 

I looked up the NGK catalogue and only the BKR5EYA-11 was listed - 

So long as the spark plugs meet the specs, then any brand should be fine, though I prefer to use the recommended brand. 
 

Sometimes Toyota and Denso change the spark plugs, like my car used to have Denso SC20HR11, then they changed to SC16HR11 and discontinued the original SC20HR11. 

 

 

[mrfixer 118]

K16R-U11 is the factory-fit plug for this engine. Its a standard plug. Iridium is an upgrade..  Denso IK16 is the Iridium version. I have these in my Avensis.