Which spark plugs??

[Marshffs]

Hello all, my 2001 wrx is due a service, at the moment it has an intermittent missfire type problem, bogging down etc. It doesn’t do it all the time and im assuming its the plugs but im changing them anyhow as part of the service. 

Question is, would you recommend NGK PFR7B and do they come pre gapped?

i have no CEL light in the car either. 

Steve

[savage bulldogs]

Heat 6's are what most use in stock scoobs and generally, heat 7's in mapped with bolt ons . If your running over stock boost tighten the gap a little to 0.65mm, to lessen the chance of spark being blown out by boost . Otherwise i think they're 0.7mm outta the box

 

Check your coilpack insluation and wires for cracks , seeing as you have a minor misfire [emoji6]