Misfire, High Hydrocarbons, what is happening?

Okay my problem is symptoming misfires.

I just got inspection done and my hydrocarbons are wayyyyy up.First time this has happened.



Here's what is good on the truck, or recently changed:

*Timing Chain

*Ignition coil

*Wires, plugs, cap and rotor

*EGR valve

*Fuel Filter

*Fuel Pump- non-electric

*Distributor does not have the side piece with a vacuum line attached-this model runs it to the computer,

which is where the canister is- with the vac line attached.

*New pickup in Distributor at correct gap requirements.(It's a single not dual.)

*New computer also.

*No O2 sensor!-it doesn't have one that I can find and I HAVE looked the whole exhaust system over.

Transmission fluid and filter just changed.



This truck had mostly original manufactured parts- as they are going out I replace them with new ones.

The carbuerator is new--I do need to get it adjusted with Tachometer.

I still have yet to run a vacuum test but I've looked over the tubes and all are okay.

I have passed the emissions test here in Texas before without problems.

My compression is good in all cylinders.

Engine is 5.2 318 V8 2BBL with a Holley Carburetor 6280

I checked to see if AIR pump was working and it's pumping good steady air, the diverter is also okay.



How bad does the catalytic converter need to get before it causes trouble? I don't know how old the one I have on it is.

I don't hear any rattling noises in it.



Rear wheel drive, D150 body. I say Body because I'm not exactly sure that the engine is the same that the

truck came with as far as type of engine. The book says it has an O2 sensor but I have not seen one in the engine or the

exhaust areas,not even a plugged whole.

I've been trying to diagnose as much as possible through the Chilton or Haynes manual but as most of you

know they can be vague sometimes with particulars.

I have 10 days left to get the emission test redone without paying for it.

I need thoughts suggestions and answers.

I say again it has passed emissions before with out any fails( with a jacked up timing chain).

I'm all ears. I'm looking for answers from experienced Mechs.Misfire, High Hydrocarbons, what is happening?
one thing you failed to mention was the year of the truck,tell me that and im sure someone on here can help you figure this one out, from what you have said and done to it though it sounds like the carburetor hasn't been adjusted right on it yet,good luck.Misfire, High Hydrocarbons, what is happening?
I added the year of the truck to the post. I have been checking other forums like dodge talk and they say I have to plug the vac line to the computer to adjust the timing and the idle. I'm also troubleshooting if there is a loose ground somewhere.

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Misfire, High Hydrocarbons, what is happening?
Take it to a shop that has the equipment to tune it right.Misfire, High Hydrocarbons, what is happening?
Sounds like the carb is tuned rich and needs adjustment.