Spark Plugs

[ceebee]

Hi All,

I have a Rav 4 2005, the book says use only irridium tipped spark plugs, could I ask Why?

[bothwell_buyer]

Hi All,

I have a Rav 4 2005, the book says use only irridium tipped spark plugs, could I ask Why?

I can't answer your question exactly. However, most engines will work on any spark plug - BUT - the engine has been designed to work at its most efficient with a type of spark plug. I guess in this case its the one mentioned. Something about how the flame spread is from the plug etc within the combustion chamber. You don't want a plug that will light up the fuel mix too soon or pinking might happen and a hole then appears in the piston/s. Think I'm right in saying that.

With the turbo engine, I read that the plug will depend on the amount of boost etc - I think Dawesey has a water injection system on his turbo 3SGTE engine to help it be more powerful/efficient. With modern engines, they are more highly tuned than the old days when any plug would do as long as the gap was 20 thou give or take 4 thou.

[Hoovie]

here is a bit of info .... http://www.spark-plugs.co.uk/pages/technic...spark_plugs.htm

I think my old 1989 Celica GT4 Turbo (same engine as your RAV4, Bothy?) used Iridium plugs? they were the kind that used to cost a lot more money but only got replaced every 60,000 miles

[bothwell_buyer]

here is a bit of info .... http://www.spark-plugs.co.uk/pages/technic...spark_plugs.htm

I think my old 1989 Celica GT4 Turbo (same engine as your RAV4, Bothy?) used Iridium plugs? they were the kind that used to cost a lot more money but only got replaced every 60,000 miles

The engine would have been the same series altho I think mine is possibly the next version - 3hp more or something. I might be wrong as I'm no expert on the Celica but wish I was - lovely cars....drove 1 but couldn't get agreement to buy 1 as wife and 4 kids wouldn't fit in (main reason for buying one was to stop them from getting in!!!)

Now I remember, the 1994 Previa also had very expensive spark plugs - a mid-engined great car. However, I found why they only changed the plugs rarely - it was impossible to change all the plugs without dropping the engine out!!!!

[anchorman]

A friend of mine fitted ordinary copper cored plugs to his RAV and he brought it to me not running right. It "faltered" during tickover (you could watch it on the rev counter) and completely lost steam if you caned it. We fitted the right plugs and it cured it.

You need to remove the individual coils and for nuber 4 the LH air filter bracket has to come off.

I can show you photos if you wish.

Cheers