Prelude:

Last night, I'm driving my car and getting into boost to pass a car when POOF! the car studders and I see my boost gauge is pegged at 0psi. No big deal, I knew it was a vac line that shot off.

When I got home I put the vac line back onto were it popped off and zip tied it down.

Today while driving through town I get the p0172 code (Bank 1 too rich). I cleared it once and it came back.

My AFR's are actually looking fine to me.... 11.5-12.5 at wot and around stoich when cruising(Although, it does bounce around +-.5 AFR while cruising...)

From what I hear there are a few causes to this... Boost leaks and bad o2 sensor.

Considering I had a vac leak last night, could that be tricking my car into throwing a CEL today? I doubt I have any boost leaks, although ofcourse you are all going to tell me to search for one. I did a few logs today and nothing looked or felt out of the ordinary.

What is your take on this? Thanks.

 

Which line popped off? Try resetting the ecu by unplugging the battery.

 

i would either erase the code with a obdII scanner or reset the ecu.

 

either you still have a boost leak or you can have your injectors scaled improper.

 

Just got a re-tune and my injectors were scaled perfectly. I doubt that changed.

I only had one vac line pop off and that was right off the fuel rail area. It's back on and zip tied tightly.

I reset the code earlier and I'll cross my fingers that it won't pop off again. Otherwise I'm going to do a boost leak test.

If that comes up with anything then yeah I'll fix it.

But I think my front o2 sensor is on its way out.

 

Might be your 02 sensor, best way to find out is to clear the code and reset the ecu from the battery and then wait for it to happen again. And I would replace the clamps on the vacuum lines as well.

 

I got that couple times when my fuel trims (LTFT Mid) were out of range. Log your car and pay attention to your STFT trims.

 

Anyone else see the correlation between the vacuum line popping off my fuel pressure regulator, and my car throwing a code for being too rich?

I reset the ECU by taking the battery off. 30 miles so far, no CEL.

Time will tell though.