just changed spark plugs and new ht leads spark plugs are bosch FR7DCX Plus gapped to 0.7mm then i tried 0.9mm when i changed them over and went for a test drive i dont have the boost there now and the dump valve isnt as loud, i allso had trouble when i first put the new ones in as it would not fire up. i now have the original ones back in and still the same any help on this???

 

Sounds like you have the leads on wrong mate

 

just changed the leads back to the original ones and its ok now but no boost still and still got the knocking on top of the engine under the inlet manafold

 

The knocking under the inlet manifold sounds like it is missfiring.

What car have you got?

The plugs that you fitted are not for a turbo Subaru.

 

hi mate i was thinking that but now its back to normal why is the turbo not coming in as it has the original ones back in its a 97 wrx p reg also fault codes are 22 and 23 knock and maf

 

Is it running smoothly at idle or is the engine rocking about?