Top 20 2004 Chevrolet Cobalt Questions & Answers

The speedo needle stepper motor is defective, remove the instrument cluster and send it out for repair. This is a common problem on this year of GM all models.

The cobalt shares the same engine as many other GM cars, notably the saturn ion , chevy cavalier, pontiac sunfire, and s10 and malibu and... long list.

sounds like a plugged cat

If the booster failed the brake pedal would take a huge amount of effort to stop the car. You should have the computer checked for trouble codes if the ABS light is on.

I doubt the security system would cause the problem.Most systems prevent the starter from working as well as the fuel pump or injectors.And once the starter cranks the engine it should not be involved.

I have seen a spring on the window regulator which helps raise the window. Don't know about GM products made in the past 10 yrs.You might look at a regulator at the dealer and see if it has one and if it looks like what you saw.

You are slipping,If you are a manual transmission you need a clutch, if you are a automatic transmission, you will need a transmission rebuilt

TPS I assume
Get it fixed by a trained mechanic right away or you may have it towed away instead to repair

YOU NEED CLIP REMOVAL TOOL TO REMOVE WINDOW CRANK HANDLE.YOU NEED DOOR PANEL FLAT TOOL REMOVE DOOR PANEL HATE TO SAY DOOR PANEL HAS AT LEAST 8 CLIPS LOCATIONS 4 CLIPS AT THE BOTTOM PANEL 2 CLIPS ON BOTH SIDES DOOR PANEL. YOU HAVE TO REMOVE 2 SCREWS HOLDING DOOR PULL CUP.YOU HAVE RELEASE CLIP BEHIND DOOR HANDLE USING TRIM TOOL.IF YOU HAVE TROUBLE GETTING DOOR PANEL OFF.HAYNES REPAIR MANUAL CAN HELP.

never noticed a connection on the side of a battery before ,unless it one of them funny american batteries with the connections on the side and not on top as normal cars

after you get 1 or 2 cans of freon in it will come on.
turn cans of freon upside down to put in
will go in faster.

if this car has a sunroof the drains could be clogged with dirt

check the wiring

nothing known problem for that generation

Sounds like electrical problem. Is the electrical connector properly connected to the valve body on the transmission ? Maybe a solenoid was accidently unplugged when you had the cover off.

Air and fuel are the heart of the internal combustion procesThe engine control unit (ECU) normally regulates the flow of air and fuel into the chamber. This is the central computer which manages virtually all the internal functions of a vehicle, including how much fuel gets injected into the combustion chamber.s. The proper amount of air and fuel must enter the internal combustion chamber if the ignition is going to be successful. Otherwise, you might have a situation where your engine either consumes too much fuel or under performs.
But if the computer were to malfunction or some other problems were to exist in the fuel injection system, then it could cause the engine to receive more fuel than it needs to sustain the vehicle’s power demands. This causes the ECU to throw trouble code P0172.

You really need to invest in manuals for these vehicles you're working on. I don't think this engine has a camshaft position sensor, regardless of the diagram you posted. Does the engine run? Is there a connector there to rewire? Is there a port/opening to insert a camshaft position sensor into? General Motors used the 2.2L and 2.4L ecotec engines in several models from 2002 to 2006 (or later) that had no camshaft position sensors.

Could be bad ignition switch or some other type electrical problem . Knowing how this system works on your vehicle is the key . The ignition switch is a low voltage input to the BCM - body control module . Depending on key position the BCM knows what relays to energize and what messages to send over the GMLAN serial data net work , PCM - engine computer . Hooking up a factory or some other type professional scan tool to view ignition switch inputs to the BCM , an checking for BCM DTC'S - diagnostic trouble codes . Circuit Description Moving the ignition switch to the START position signals the body control module (BCM) through discrete inputs from the ignition transducer that engine crank has been requested. The BCM verifies that theft is not active and sends a serial data message to the engine control module (ECM)/powertrain control module (PCM) requesting engine start. The ECM/PCM receives a 12-volt signal from the park/neutral position (PNP) switch or clutch pedal start switch notifying that it is safe to start the engine. There is a splice on this circuit in the fuse block-underhood that supplies power for the starter relay coil. The starter relay coil control circuit is then grounded by the ECM/PCM closing the switch in the starter relay suppling 12 volts to the S-terminal of the starter. Ground is supplied through the engine block. Plus you need to under stand what power modding is , because the BCM is the power mode master . This will sound funny to someone who does not know about automotive electronics . Serial Data Gateway The body control module (BCM) in this vehicle functions as a translator between the High and Low speed GMLAN busses. The 2 communication protocols use the BCM to translate communicated serial data messages between the control modules over the 2 serial data busses. Power Mode Master This vehicles body control module (BCM) functions as the power mode master (PMM). Refer to Power Mode Description and Operation for a complete description of power mode functions. Power to many of this vehicle's circuits are controlled by the module that is designated the power mode master (PMM). This vehicle's PMM is the body control module (BCM). The PMM controls which power mode (Run, Accessory, Crank, Retained Accessory Power, or Off) is active. On vehicles that have several control modules connected by serial data circuits, one module is the power mode master (PMM). On this vehicle, the PMM is the body control module (BCM). The PMM receives 3 discrete ignition switch signals to differentiate which power mode will be sent over the Serial Data circuits. The 3-wire Ignition Switch table below illustrates the state of these inputs in correspondence to the ignition switch position: Relay Controlled Power Mode The body control module (BCM) uses the discrete ignition switch inputs Off/Run/Crank, Accessory, and ignition 1, to distinguish the correct power mode. The ignition 1 circuit is also routed to the Run/Crank relay for relay controlled power feeds during the appropriate power mode. The BCM, after determining the desired power mode, will activate the appropriate relays for that power mode.

Sounds like the ignition key mechanism has failed. Probably needs replacing. Has anyone been attaching wires to it? If so, they may have mixed up the wiring.