93' California Blazer 4.3L 105K. I have had some problems over the years with spark plugs carbon fouling out. I've listed it a few times as spark plugs fouling out. Besides the regular spark plugs, wires, dist cap and rotor, fuel filter, Fuel Pressure Regulator,air filter, O2 sensor, and also replaced the Cataylic Converter because it was rattling. I recently also put in the screened EGR Valve gasket to help stop large chunks of carbon from getting up in the EGR valve and holding in open.

So today I took the car to have it smogged (California Car)it did pass but I noticed that the levels for the car overall were per good except for the HC (PPM) which seems to be a little high but withing the correct level to pass. So here's the readings. The First set is the old 2006 California Smog test. Notice the HC PPM then is at 58 top spec is 89and AVE is 18 Then the bottom set is the current 2009 test HC is 76 spec is still the same Top 89 AVE 18. So my concern is the engine runing to rich? In 2004/5 they replaced I believe my CPU for a recall on the ABS. I wonder if maybe there are parameters that needed to be set for fuel that maybe were never set correctly? Are there parameters like this that are adjustable with the computer? I haven't pulled the spark plugs again yet. They have about 250 miles on them. Well in any case what would cause the HC PPM to be on the high end?

2006


2009

 

There are no parameters that must be "programmed" in terms of fuel delivery. The system is adaptive, adjusting itself to the conditions to maintain proper fuel to air ratio.

 

If I understand the read out correctly the AVE should be around 18? So it seems that the engine is putting out more than it should even though it passed at 76. I'm just trying to find out what a higher than normal HC means.

thanks