1988 emissions test failed

[442-troy]

100% stock Lg4 305, no service engine light, has had a new cat, carb, tune up parts and egr installed by previous owner. any tips on where to start to get my e-test pass? Ontario is a 2 speed idle test for old cars, idle and 2500rpm. I tried some methyl hydrate , GRC guaranteed to pass and had the car nice and hot for the test. thanks for any help

 

[pontiacgp]

You're running lean at 2500. How old is the 02 sensor

 

[442-troy]

You're running lean at 2500. How old is the 02 sensor

I believe it was changed in 2008.

 

[pontiacgp]

I would try another 02, it may be getting slow to react...