Technical Spark plugs

[Mark2]

Hi all
I have a 2003 2ltr ulysse duel fuel and all of a sudden it has developed a miss fire would it be the spak plugs as nothing comes up on lexia3.
Thanks
Mark

 

[FRANTIC FRAN]

When was the last time the lpg system was serviced?

 

[Mark2]

I don't no it was on when I got the car it misses when on petrol as well as lpg