2009 2.2L Pontiac G5 Comes up code P0641 What does this mean? Thank you

When this light comes on it means the computer control module has detected a fault in the system, it has reduced power to avoid any damage to the engine or transmission. You must now have the computer scanned for fault codes, this is done through the diagnostic connector under the dash see photo below.

I have an 2004 Grand Prix with 181,000 miles on it and recently got the Reduced Engine power light and codes p0068 and p0101 after searching the web I wound up cleaning the the throttle body and MAF sensor with no luck, but after finding out where the fuel filter was I changed it, which cured the problem. How embarrassing, I have owned this car for 9 years and have had it serviced regularly, but never before changed the fuel filter. I sure the other stuff helped but the fuel filter fixed the reduced engine power problem. I had to disconnect the battery each time to get it out of limp mode and was quite frustrated at the end.

Fuel pump is bad.

It means the same as any time you get
any MIL lamp on your dash
You have a shop check for codes & diagnose
the issue

My code on my van P0641 does anybody know what that mean

You need a new personal mechanic. When many codes come up, that means he detected many problems and his head started to spin like Beetle Juice. Find someone that knows how to interpret the meaning of those codes and do the correct repairs.

Having same problem with reduce engine power, good engine hard to pin point without pros.After driving awhile discover blown intake manifold gaskets..take awhile to show external signs.Remove throttle body...if gasket inside is wet then start there.Let me know how it turns out uh.

DTC P0641 The powertrain control module (PCM) provides a 5-volt reference to the following sensors:

The throttle position (TP) sensor 1
The accelerator pedal position (APP) sensor 2
The engine cooling fan speed sensor
The AC pressure sensor
The fuel tank pressure (FTP) sensor
The oil pressure sensor (OPS)
The PCM monitors voltage on the 5-volt reference circuit. If the voltage is higher or lower than required, DTC P0641 will set.

Conditions for Setting the DTC
The PCM detects a voltage that is higher or lower than required on the 5-volt reference circuit. The above condition is present for 1 second. Action Taken When the DTC Sets The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails. The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame/Failure Records.
Conditions for Clearing the MIL/DTC The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail. A current DTC, Last Test Failed, clears when the diagnostic runs and passes. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic. Clear the MIL and the DTC with a scan tool.

Yes i can be dangerous, depending which issues mentioned above has triggered the code such as a faulty gas peddle position sensor. the code can also cause a reduced engine power to activate.

Thank you for using Fixya and best advice is to have the dealer address these issues. A tech 2 scanner would be needed to address the P0641 DTC code.

they had to tell you something,you wouldn't just hand over money with out an explanation .can't help with out knowing codes

hi there my name is don i will try to help you on this
when your reduced engine light comes on that means there is a active fault code in one of the sensors that is cusing this
you will have to get it scanned or retreive the codes from the dash

once you shut it off and turn it back on it temporarly resets until the diagnostics go through it again and it will reduce the power to the engine
it could be something simple like a gas cap or tire pressure but you will have to get it scanned to find out
thanks
don