my car will work fine some days and other days it will hardly run at all. this has been happening for about 2 weeks. it will either surge and all of sudden die when i am just cruising it or when i get into boost it feels like it is missing. i have tried replacing the fuel filter as well as using fuel injector cleaner or fuel treatment cleaner still not helping. any ideas? would this be a bad injector(injectors are svo 42s and have about 5k on them)?

 

I would check both of these:

1) The fuel pressure at the rails - it could be the fuel pump is failing.

2) The distributor control module - these go out sometimes (about $30 at autozone)

I've had both of these fail on me and, when they do, the car barely runs or dies when running.

Hope this helps!