p8ntballkid090

Hey guys,

I have an 01 Camaro LS1, with just cold air intake and exhaust. My headache started with replacing the knock sensors. Now I have the rich codes P0172 and P0175. The car idles really rough until it goes into closed loop. It stalls if try and drive it in open loop.

I've replaced the MAF, MAP, and IAC. I cleaned the throttle body, new intake gaskets, replaced all the PCV rubber lines, checked the EVAP valve.

After all of that it led me to check the fuel pressure at the rail, fuel line, and injectors. I listened to each injector and I can hear each one clicking. Then I checked the pressure at the rail and the fuel feed line. Both went to 60psi and dropped to 10psi within a minute, which I believe means a bad fuel pressure regulator.
Here is a vid of the pressure at the metal fuel line in the engine bay.

With the fuel regulator in the tank how could this cause these rich codes? Or is this another issue and its the injectors causing the rich code?

Any help would be great!

LSX Power Tuning

iTrader: (4)

If it started after you replaced the knock sensors I would look at the intake very close. I have seen a couple times over the years where people got the harness pinched under the intake and ground out the map sensor.

p8ntballkid090

I have a scanner that can view the PID live data and the new MAP sensor is reading normally.

2xLS1

iTrader: (25)

What are the fuel trims showing while running? Both ST and LT. Also an EVAP canister that is saturated can cause a rich condition.

2xLS1

iTrader: (25)

Pressure should hold a lot longer than that. Lift the rail with the injectors still attached to it and perform the same test. Look for any injectors leaking. If they are not I'd say you have a problem with the pump assy in the tank.

p8ntballkid090

The highest I've seen the short term is -34. Once the car warms up it settles down to around -15.

The long term has been hanging around -7 to -10 normally.

p8ntballkid090

To narrow down if the evap canister is causing the problem. Could I disconnect the evap line at the intake and temporally plug it to see if that resolves the issue?

2xLS1

iTrader: (25)

Sounds reasonable. Here is a little more info in setting those codes. It's all about the negative fuel trims.

CONDITIONS FOR RUNNING THE DTC

DTCs P0101, P0103, P0108, P0135, P0137, P0141, P0200, P0300, P0410, P0420, P0430, P0440, P0442, P0443, P0446, P0449, P0506, P0507, or P1441 are not set.
The Engine Coolant Temperature (ECT) is between 75-115°C (167-239°F).
The Intake Air Temperature (IAT) is between -20 and +90°C (4-194°F).
The Manifold Absolute Pressure (MAP) is between 26-90 kPa (3.7-13 psi).
The vehicle speed is less than 137 km/h (85 mph).
The engine speed is between 400-3,000 RPM.
The Barometric Pressure (BARO) is more than 74 kPa (10.7 psi).
The Mass Air Flow (MAF) is between 5-90 g/s.
The fuel level is more than 10 percent .
The Throttle Position (TP) is less than 90 percent.

CONDITIONS FOR SETTING THE DTC

The average long term fuel trim value is below - 13 percent.
All of the above conditions are present for 40 seconds .

warriorpluto

iTrader: (2)

Well? So what happened? I just had this code pop up today. New intake gaskets, knock sensors and Delphi maf I installed last year. I would love to resolve this but don't know where to look