holy hell that would suck!

i checked my valve springs visually and i could not see anything wrong with them. you think its possible that one is "bad" but not broken?

 

and your converters are good?

 

Yessir, a spring can be weak but still be in one piece...very hard to diagnose...

 

With a weak spring wouldn't the misfire get worse or show up only at higher RPM or in boost?

 

Funny you mentioned it that way because that is exactly what it has done. Started as a top end miss and progressed. Only problem is I swear its a mulitiple cyl. missfire and what are the odds of having multiple springs getting weak with hardly any miles on them? Of course they are 918's so who knows. (new batch)

 

I'm going to agree with this. A "weak" valve spring wouldn't affect idle in my opinion.

 

Mine has been driving me nuts too. Misfire in boost only, no misfires in the logs. Checked/changed everything twice! Tonight I thought it was time to check the catch can after 3-400 miles on the motor. Damn thing was full. Who knows how long it has been that way?? Hope I found something.

 

Yessir you are correct (at least in my experience)...I thought that is where the problem was? (guess I should go back and reread the original thread...it's been floating here a while and I guess that I forgot where the original problem was, sorry, my bad )

 

I checked my catch can, some oil in it but not even 1/4 full. Keep us posted...

 

Sorry that I didn't reply earlier.

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