I need some help here. 91 350 has failed smog a few times now. I am at a loss for what could be wrong as the car seems to run fine. This latest time it failed was for high HC. Does anyone know of a good shop in the Chino Hills area that could look into this?

Thanks
Steve

 

HC is unburnt fuel, IIRC. Start with the simple stuff like your timing. How long has it been since you changed your plugs, wires, rotor, and cap?

 

so i have about 270,000 on the original motor. It first failed smog back in 2013 and since then I have not even put on another 2000 miles. In that time, i have replaced the distributor along with cap and rotor, map sensor, new fuel injectors, fuel pressure regulator, fuel pump and plugs. the cats have about 3000 miles on them. other than the engine just being worn out i just don't know what to do with it anymore. The engine feels like its running fine

 

smog pump?

Try this:

http://www.smogtips.com/failed-high-hydrocarbons-HC.cfm

 

I did replace the smog pump recently and all 3 of the valves that go with it. How can I test if the pump is working correctly?

 

Here you go:

 

By how many points on the HC did you fail? I just failed mine by two stinking points.

 

What injectors and fpr did you put in the car? Im close in ontario and can look at it for ya.