1995 exhaust/emissions help

[m3f_fuse]

Hello all-



I have a 1995 Alpine White M3 with about 109k.



I bought it used not quite two years ago. Its been rock solid, but the dealer indicated when I bought it that it failed emissions but they fixed it.



I did not pass emissions last year, but an Inspection II service enabled a pass by basically a single point on hydrocarbons (I think).



I'm coming up on the annual emissions test and concerned I'm not going to pass.



Two questions:



1) Any ideas on a real root cause?



2) Failing being able to answer #1, any ideas on whether or not exhaust changes from the block back ( exhaust manifold, cat, something like a borla cat back) would improve the situation?



Any and all advice appreciated. Thank you!

[m3f_SG_M3]

is the car going in cold? is it sitting long before they test it?



If yes, then it can fail. You should run it at high rpm's, and get the cats very hot. Then get it tested ASAP.

[m3f_salty]

Adding to Sean's reply, a crankcase full of fresh oil can reduce your emissions come test time.

[m3f_orijinal_poser]

i recommend Seafoam. a can of Engine Restorer wouldn't hurt either. but definitely try seafoam.

[m3f_NorCal///M]

high levels of hydrocarbons can be an indicator that the catalytic converter needs to be replaced... definitely change oil & plugs, and ensure that vehicle is completely warmed up.

[m3f_fuse]

Thanks to all for the input, greatly appreciated. :-)