Running rich and P0172

[Bipod]

Okay, I've been gitting this code for a couple months... I smell gas for a day or so, and then a day later this code comes. I went to Autozone and got the standard "you need new O2 sensors" response. Is there a problem running with this code (other than burning thru gas really fast) and are there some solutions I can try? Just FYI... the S has new OEM injectors and plugs about 8 months ago and a new fuel pump about 6 months ago. She's blown with a Comptech S/C and has 54xxx miles. Thanks!

[repiv]

A situation such as yours is further complicated by the fact that you have a supercharger.
Generally, when this code pops up, it can be associated with MAP sensor codes, O2 sensor codes and EVAP cannister codes. Were there any other codes showing up concurrent with this one? It might be necessary to direct some attention to the MAP sensor doing the old "MAP whack" thing. More appropriately would be to ensure the wirng harness is firmly secured with the zip tie mod. Perhaps even consider taking off the MAP sensor and the intake from the front of the throttle body and cleaning the MAP sensor orifice with some WD-40 and compressed air.
The EVAP cannister may be what's causing the smell and this can be associated with fuel pressure (too much pressure) or a bad purge valve. I have the Vortech and I too, can smell gas from time to time. My A/R gauge indicates that I'm running a bit rich at times, but since it's supercharged, it is within a range that I'm comfortable with. Better to be a bit rich than too lean when S/C'd. However, I've never thrown a code as you have. It is possible that your fuel pressure regulator (Comptech one) may be ramping up the pressure too much. If you are really concerned, you might want to have the A/F data recorded. The regulator can be modified to reduce the fuel pressure a bit, but this process shouldn't be attempt unless you are on a dyno and know exactly how much to turn the screw.
In case there is some relevence, why did you need new injectors and a new fuel pump months ago? Running rich like that is not a dangerous condition except that it might shorten the life of the O2 sensor and cat. converter. Of course, the smell of gas can be annoying. If it gets way too rich, the CEL will blink, but I can't imagine that it would get so rich as to make the ECU think it's an unsafe condition. Too rich means you are not optimising the power output of your engine even though it is giving you a big safety margin. A side effect of running too rich is that the plugs foul easily and sooner. What gap are you running? It might be too narrow, especially if you not "on it" much. The typical gap for a Comptech blown engine is approx. 0.034" (+/- 0.002"). You might try to increase the gap ever so slightly if the kind of daily driving is more sedate and you don't use the supercharger at boost (high rpm) often.

[Bipod]

Thanks for your insight Dave! As for the new injectors and pump... I was getting missfire codes all the time that weren't consistent. So at the dealer they suggested the plugs were fouled, and then a week later more missfire codes and they said the injectors were so full of gunk they wouldn't come clean... then a couple weeks later missfire codes again... took it to SOS and they dyno'ed and said the A/F was way lean on the VTEC swith over that my pump wasn't delivering the fuel fast enough... so new fuel pump. Been running great ever since. I run just the stock gap on the OEM NGK plugs. I don't really get on it too much in the summer time since it runs really hot with the S/C and I don't have an aftercooler (yet :D). So my daily driving is rather mundane... I will try the MAP whack since I've never done that (I'll try to dig up the instructions here on the site) and maybe do the clean out. Is there a real need to change the plug gap?

EDIT: No other CEL codes with this one. Oh, and I replaced the gas cap recently too, since I had gotten the code for "fuel system can't pull vacuum"...

[repiv]

Is there a real need to change the plug gap?
That's up to you. The whole premise behind narrowing the gap on a FI engine is that under boost at high rpm, if the gap is too wide, the spark "blows" out and you get a misfire. Maybe that's what your original problem was. I can't be sure. It's a bit of a compromise. The stock gap (being a bit too wide for FI) increases the risk of spark blow out and hence, misfires. Having too narrow a gap will increase the chance of plug fouling, especially if you don't take it to high boost very often.
Ideally, a FI engine should be running just a little less than 0.030" gap, but since we don't always run it up to high boost, we compromise by picking something in between (like those numbers I stated in my last reply).