Spark plug recommendation for 2003 4.6is

[onedaymyfriend]

Hi guys, which spark plugs would you recommend for a 2003 4.6is?

Thanks in advance.

[henrym3]

I have been using Bosch, can’t remember the code but they are the 4 prong ones. Been in for 25k and 90‰ of that mileage has been on LPG. To and from work 16 mpg, long runs are 18mpg, has dropped of recently to 15 mpg and am about to fit LPG plugs to see how it goes.

[lezmtaylor]

Henry, will be interested how the lpg plugs go, although the standard plugs fitted 25k ago are still ok and I use the lpg 100% except for starting.

Lez

[henrym3]

I read that they are less demanding of the ignition system so thought I’d give them a try. I’ll keep you posted. Don’t know if it’s related to constant use of gas but looked at the crankcase breathing system today which I renewed 4 years ago and the pipe insides are like I fitted it a week ago.