89 Accord emission failed in CO test 25/25

89 Honda Accord failed for emission test for CO, in both 25/25 and 50/15
catogery. I replaced the air filter and used car guarantee pass and drove
300 miles. When I took my car back for emission test it passed in 50/15,
but failed in 25/25, here are results

Test 1 --> 2.66 -- (1.16 allowed) FAILED--> 2.83 – (1.05 allowed)
FAILED
Test 2 --> 1.91 – (1.16 allowed) FAILED --> 0.12 - (1.05 allowed) PASS

Can anybody suggest me what are the things I can fix and test for
emissions again? Since it passed the 50/15 test I was hoping this is a
minor problem.
I am planning to change spark plugs and PCV valve.

Thanks

i would do the fuel filters, air filter, pcv, plugs, distributor cap, put
some sunoco 94 octane in it. all the cheap things that are easy to do.
change the breathers on the side of the air filter housing too.
"rajakaraja" wrote in message

 > 89 Honda Accord failed for emission test for CO, in both 25/25 and 50/15
 > catogery. I replaced the air filter and used car guarantee pass and drove
 > 300 miles. When I took my car back for emission test it passed in 50/15,
 > but failed in 25/25, here are results
 >
 > Test 1 --> 2.66 -- (1.16 allowed) FAILED--> 2.83 - (1.05 allowed)
 > FAILED
 > Test 2 --> 1.91 - (1.16 allowed) FAILED --> 0.12 - (1.05 allowed) PASS
 >
 > Can anybody suggest me what are the things I can fix and test for
 > emissions again? Since it passed the 50/15 test I was hoping this is a
 > minor problem.
 > I am planning to change spark plugs and PCV valve.
 >
 > Thanks
 >