Hi all


Just fitted some of the above plugs on a slightly moddified MY92 legacy turbo and on cold days when the engine is also cold, it misfires and pops and bangs like a bugger until its fully warm and then it behaves like a dream, even if the engine is mildly warm it will behave fine. Its so bad that it will no idle without stalling. The gap is 0.7mm and all the coil packs look fine and it was fine cold or warm with the old plugs which were PFR6B.

Do you think the 7 heat range is too cold for the car??

Am i best sticking to 6's instead. Any help much appriciated thanks

 

7's should run cooler so you would get oil build up on them if they were too cool. I know many people run 7's on imprezas without any problem (I do), but they are the PFR7B's.

I tried an iridim plug on my car (BKR8EIX) with similar results that you are finding, and an expert told me it was not the temp rating of the plugs that was the problem, but just that 'that type' of plug did not work well with the coil packs (?).

I don't know much about the legacy engine but if it is the same as the early impreza (mines a 1994) then I'd advise you get the PFR's and stick to heat rating of 7

(forgot to mention - mine idled very well on the badly performing plugs, just could not boost)

 

Thanks for that, i may just revert to the PFR's like you say. Its a real pain!

 

Just to clarify, what if the difference between the BKR7E and the PFR7B plug??

 

the PFR is a platinum plug, just one heat rating different to the std - run/supply loads of them you'll not see any downsides.................

alyn