My car stopped picking up speed

ANSWER : Hi there. Check the turbo on the engine. With the loss of power until the vehicle is driven normally after 100 meters and the lack of power going up steep hills, the turbo could have failed causing the engine to lose power. Remove the intake hose to the turbo and start the engine. Look to see if the turbo is spooling up or not. If its not spooling up, then the turbo shaft could be seized and would need replaced other wise the waste gate could be not functioning causing the turbo to stop boosting. I recommend seeking out a professional, such as one from Your Mechanic, to help you diagnose your loss of power.

ANSWER : The A/C thermal expansion valve (TXV) most likely is the cause of the A/C system freezing up at higher engine or vehicle speeds. The TXV controls the flow of refrigerant through the evaporator and the valve can stick open causing the system to not get cold after it opens or the valve will stick on an almost closed position and cause the orifice to freeze up and cannot control the correct amount of refrigerant flow through the evaporator. The A/C system should be performance tested and checked for pressures to make sure the system has enough refrigerant or the TXV is the cause of the problems. The TXV is mounted to the evaporator and can be replaced separate from the evaporator. If you would like to have this inspected, a certified technician from YourMechanic can come to your car’s location to diagnose the AC issue in person and pinpoint needed repairs.

ANSWER : Hi, thanks for writing in. I’d be happy to try to help. It is hard to definitively diagnose what the issue is. At first it seems like a transmission issue. Automatic transmissions are rather complicated and can do strange things when they malfunction. If not an issue with the transmission, you could also have a clutch issue. Always start by checking the simple components first. Check your transmission fluid level. Make sure your transmission filter is clean and debris free. When you have the transmission pan off, you can look and see if there are any metal shavings at the bottom. There is often a small magnet at the bottom of the pan designed to gather any metal shavings for a quick diagnosis. This is a sign of more serious transmission problems. Unless you have experience with automatic transmissions, it is not recommended that major repairs be done at home. I suggest taking your car to a transmission specialist for help.

ANSWER : Hi There,
It sounds like you may have a dirty or faulty mass air flow sensor. The problem this can cause may also be compounded when the engine is cold due to the change in air density in cooler weather. The mass air flow sensor monitors air intake as it is mixed with fuel prior to being injected into the motor. This sensor relays information about fuel and air temperature, air speed entering the motor and many other things to the ECM which uses this to make adjustments to fuel supply to the motor. A dirty or faulty sensor can cause an imbalanced air/fuel load to be supplied to the motor which results in an over fueling or under fueling situation depending on the conditions. This type of inconsistent fuel supply to the motor may cause a hesitation, loss of power, a jerking reaction, potentially a bit of black exhaust smoke and typically a strong smell of fuel when this sensor is malfunctioning. I would suggest having a professional from Your Mechanic come to your home to diagnose and inspect your vehicle.

ANSWER : It sounds like you may have a dirty or failing idle air control valve. The idle air control valve monitors the air intake as it is mixed with fuel prior to being injected into the engine at low speeds and at idle. This valve is controlled by the vehicle’s computer and will adjust idle speed based upon other measurements such as engine temperature, intake air temperature and electrical system load or voltage. This is also an important function when starting the motor as it allows the motor to run and idle on it’s own once the motor fires. When you accelerate, the engine RPM increases, and as you let off the gas, the RPM slowly returns to the normal idling speed with the help of the idle air control valve making the transition from a higher RPM back down to idle speed while adjusting the air/fuel ratio constantly to allow this to happen smoothly. When the engine RPM drops below the normal range of about ~800 RPM, this often times will cause the engine to stall indicating a dirty or faulty idle air control valve. I would recommend having an expert from YourMechanic come to your location to diagnose and inspect your vehicle.

ANSWER : Hi and thanks for contacting YourMechanic. All three codes refer to the pressure control solenoid in the transmission. Check the fluid level and top it off if the fluid is low. Check the harness to the transmission for any corrosion, moisture, oil, or any broken / bent pins. If the fluid is good and the harness is good, then you will need to replace the pressure control solenoid. If you need further assistance troubleshooting your transmission, then seek out a technician, such as one from YourMechanic, that can diagnose your vehicle’s stalling problem and assist with repairs.

ANSWER : Hello. Warning lights accompanied with stalling can be caused by many things. If the oil is low I would go ahead and top it off to prevent the possibility of engine damage, however, it is unlikely that low oil is what caused the stalling. Stalling is most commonly caused by issues with the ignition, engine management, or fuel systems. If one of the components, such as a major sensor, the fuel pump, or the ignition coil, go out or have an issue they can cause the engine to stall. If the vehicle is no longer starting then it may be possible that there is an issue with the electrical system as well, perhaps a faulty battery or alternator. If the alternator goes out it will eventually drain the battery, which could also cause stalling. Scanning the computer for trouble codes, once the vehicle is started, will likely reveal some insight into what the issue may be. As the possibilities could be many, I would recommend having a professional technician, such as one from YourMechanic, come to your location diagnose what may have caused your vehicle to stall.

ANSWER : Hi there – you may have 2 related events here, a coolant leak, and a problem with the heater system. The current issue may be air inside the cooling system, which can cause overheating, and a lack of heater function. The lack of heater function could have 5 causes: the engine is not getting up to correct temperature (center of the gauge) due to a malfunctioning thermostat, the heater control valve is not letting hot coolant into the heater core, there is a restriction in the heater system that is preventing adequate hot coolant flow through the heater core, the heater fan is not working to transfer heat from the heater core to warm air for the passenger compartment, or the air blend doors inside the heater are not working properly to route warm air to the desired vents. I would recommend a heater system inspection](https://www.yourmechanic.com/services/heater-is-not-working-inspection) by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, give you an accurate assessment of damage and cost estimate for repairs.