My 420 SEL Failed VA Emissions - Help Please

My 1986 420SEL with 224,762 miles has failed VA emissions. Here are the test results:
15MPH Test Test Limit Reading Result HC ppm 65 149 Fail CO% 0.26 0.23 Pass
NO ppm 857 375 Pass RPM 1304 Valid Dilution 14.6 Valid
25MPH Test Test Limit Reading Result HC ppm 119 229 Fail CO% 0.38 0.35 Pass NO ppm 833 623 Pass RPM 1240 Valid Dilution 14.6 Valid
Visble Smoke Inspection Pass
My question is: What would cause high HC readings and what are some things I should be checking for? Thank you T.C.
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Worn spark plugs, old ignition wires (cause weak spark) can cause high HC reading. Also retarded ignition timing.
When was it last tuned up?
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How about a catalytic converter that is shot, or excessive oil slipping past the rings/valve guides?
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That's also a possibility, but no oil consumption was mentioned.
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Thanks for the reply. That's exactly what the inspection tech said. I replaced the plugs, wires, cap, & rotor exactly 5 years ago (about 60,000 miles) and haven't touched them since since the car has been driving fine. I will go ahead and change all these out.
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I would just change the plugs and O2 sensor... cap and rotor are good forever... well pretty much that long.
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wrote:

Where in Virginia are you having the car inspected that they're doing tailpipe tests? I've lived in Norfolk for eight years, and have never had to have any of my bikes or cars emissions-tested as part of a state inspection (model years vary from 1972 to 2000).
Since your car has probably been flagged as an "inspection failure", you'll have to get the emissions back within acceptable limits before you can get an inspection sticker this year, but I would suggest that for future inspections, you take a road trip to a part of the state that doesn't do tailpipe tests.
--
Scott Gardner

"If you sleep twelve hours a day, then the deployment will only be three months
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<snip>

Uh, Normally it doesn't work that way. If you live in the more populace area, you need to have you vehicle tested. Some people will dodge this by having the car registered at a more rural address...
I have been told that in the event the HC emissions are coming from oil leaking in the cylinders, that Mobil 1 will pass the emissions test for you. This is strictly hearsay, so don't blame me if it doesn't help...
Marty
PS I agree with TG that a tune up is the proper place to start.
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On Tue, 13 Sep 2005 23:22:37 -0700, Martin Joseph

I found out the emissions testingin Virginia isn't based on population (or else the Norfolk/Virginia Beach area would have it for certain). Rather, it's just five counties and five cities in Northern Virginia that have the emissions testing. It's not part of the regular state inspection, and it's tied into the DMV database so that you can't register the car until the emissions test has been passed.
If your vehicle fails the initial test and the re-test, you can get a waiver, but only if you can show you've spent at least $620 trying to fix the problem. At least you'll only have to deal with it until the car is 25 years old.
So, it looks like the best thing would be a full tune-up prior to the re-test. Make sure the engine is up to full operating temperature before you have the test done. Also, change the oil immediately before the test to minimize the amount of unburned hydrocarbons present in any oil that seeps past the rings into the exhaust.
Best of luck,
--
Scott Gardner

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