psi would be above zero. in. Hg would be below zero

 

you guys were right. clogged cat! im hoping thats not a real serious thing.

 

^ buy a new DP (larger diameter). Get it with or without a cat...but i dont know of any aftermarket cats getting clogged on our cars. its maybe $100-$150 depending where u go. I wouldnt buy a stock one though, since theyre so prone to clogging (as you now know from experience)

 

well im in the market for a new exhaust. im getting headers back. ill live with the light for a little longer.

 

check vac lines.. if it was fine before obviously something went wrong with install..... i dont think the cat clogged in 1 day and happened to be in between intake changes