My car won't pass smog

Question

I have a 87' Ford Escort Gl With C.F.I and at an idle it failed the emissions test. It was 20 over the limit (Hydrocarbons) and I have put new sparkplugs, plug wires, cap, rotor, vacumn hoses, catalyitic converter, ran blockseal through it incase there was a head gasket leak and ran engine cleaner through it. At 2500 rpm the hydrocarbons were at 19. Any ideas on what the problem could be?

Answer 1

O2 sensor may be bad.

Answer 2

I had a similar problem on a '83 Mustang. Rebuilt the carburator and a new set of gaskets got it back on the road.

Answer 3

did you double check timing?  

Answer 4

Very good diagnosis, especially among other question on here who leave no details.  Hydrocarbons, means fuel.  Not even unburnt fuel, meaning CO.  Your very close to passing, but hard to say what it is, without an inspection.  The only thing I can think of after doing plugs, cat, vacuum check, rotor, cap, and wires is possibly a compression check.  Check both static and running.  Ocassionally you will get low compression on a cranking test, but not on a running one.  Could be the rings.  Another situation, which usually leads to high Nox is carbon buildup on the piston tops, and valves.  You can de-carbon by buying a kit, or even lightly spraying distilled water while revving at around 3000rpm.  water provides a cooling and decarboning effect.  

Honestly if your high in HC's its a mechanical error.  My guess which is the best one could do without diagnosing is... To check timing, and also camshaft timing belt alignment.  

Somehow you are getting totally unburnt fuel past the combustion chamber, and into the exhaust to reach the o2 sensor.  This means you are running either extremely RICH, or something is seriously off.

Answer 5

sounds like you have done your homework. well check your compression and see if your rings are worn. those weren't very good cars to begin with i'm really suprised you still have one an put money in it.  kudos to ya