hello
I have a 1994 accord ex with 282000 miles
tried to smog it and failed
about 12000 ago I did the head gasket

15mph 1664 rpm
%co2 meas 14.9
%o2 meas 1.0
HC (ppm) meas 188 max 61
CO% meas 0.42 max .51
NO(ppm) mean 663 max 490

25 mph 2653rpm
%CO2 meas 15.2
%02 meas 0.1
HC (ppm) meas 33 max 36
CO(%) meas 0.12 max0.49
NO(ppm) meas 156 max 730
my question is where do I start
does timing cause a big difference ?
valve adjustment?
before I went to smog changed the oil and filter
cleaned air filter k&n washable
plugs
and drove around for 15 minutes before taking the test..
any advise would be helpful
thank you

NEW INFO
I found an exhaust leak at the manifold to down pipe connection
would that cause the high numbers
also did a compression test 135psi all 4

 

No CEL?