High Hydro-Carbon Reading - Interesting Outcome!

Shark56

SILVER Star
Joined
May 12, 2005
Messages
1,016
Location
Dover, DE
Time for my 74 to get inspected. It has a 2f and a 79 electronic ignition in it.
In Delaware we have actual DMV facilities that do the inspections, for a total of four inspection places.
I head down Tue. to run it through the inspection lanes. As I'm heading there, after a quick stop at Lowes, I notice my idle is rough.
As I pull into one of three lanes open it is barely idling...🤬
Oh well, I will get the safety stuff done and worry about emissions later.
The reading for HC was about 5 times the upper limit according to the computer.
Safety check is all good so I would need to bring it back for a re-check of emissions.
Start heading home, 20 mile drive or so and truck continues to run worse. Finally bad enough to pull over and check what the heck was going on. Checked a few things and decided to pull distributor cap. Sure enough, plenty of carbon build up. Cleaned it contacts and rotor off with my fish hook file and fired it up. Ran much better. Since I knew I had a new Cap and Rotor at home I went home and swapped them out. Ran it back through emissions today and had a substantial drop. Hard to believe that much difference a new Cap and Rotor made. I made no other changes. Cap and Rotor had about 12 years on them with maybe 10,000 miles.
Passed inspection and a little less than $200 🤬 has me good for two more years.




20211014_124342.jpg
20211014_124315.jpg
 

pjohnson

SILVER Star
Joined
Jan 15, 2003
Messages
2,626
Location
Idaho
Not really too surprising...
Poor electrical conductivity = poor spark = poor burn = unburnt fuel in exhaust = high hydrocarbons

Nice that it was an easy fix 😉
 

Users who are viewing this thread

Top Bottom