Can the stock fuel pressure reg fail so you run lean.My car is running lean and getting some knock. I am sure its real knock retard not false.I am running 92 octane which should be plenty at my 1900 feet altitude.

What would happen with a leak on the line to the reg or line disconnected.That would make car run rich right? Also I have vac line to my egr disconnected ,will this also lean the car out? I run no egr in my talon or 99 ta no problem but mabye the lt1 needs it to work? I tried to go richer with my maft but still the car seems to lean out sometimes and get knock .And maft is not even connected now and its still doing it. I know I have to check fuel pressure ! Will do that shortly.

So anyone have a dud regulator and what did it do?

 

Is your Vac line that you disconnected from the EGR plugged up? That will cause you to run a little bit lean since its a small vaccum leak.
The car's O2's should also adjust your car to normal if theyre working right. Perhaps your o2's are not working right any more? Fuel pressure looks like the best bet, perhaps your fuel pump is dying though if this happens only at the higher rpm's

Hookup a fuel pressure guage (tape it to the windshield) and see if the readings are normal. THere should be lots of posts with what the proper fuel pressure should be.