Rough engine idle lights flicker loss of power PT Cruiser 2007 Turbo

ANSWER : It sounds like you may have a weak battery, a failing voltage regulator or failing alternator. As you may know, the alternator charges the battery while the engine runs by generating amperage and recharging the battery while the engine turns the alternator pulley. The voltage regulator is a unit that regulates the charging of the battery by the alternator and maintaining a certain amperage while the engine runs. When the alternator is not working properly, this may result in the battery quickly losing charge and the car losing all power. You may also notice a whining sound as a result of the bearings inside the alternator begin to fail. I would recommend having an expert from YourMechanic come to your location to diagnose and inspect your charging system.

ANSWER : Your car has what is called a "safe mode" that will be engaged by the computer when it detects that something critical has gone wrong related to any of the major components in your engine chassis or power train. This may be related to a number of things, most of which should have been registered in the computer when the check engine light came on. I recommend having an expert from YourMechanic come to your location to inspect your check engine light and diagnose any codes registered by your vehicle’s computer.

ANSWER : The issue you are writing in about is common enough that a specific diagnostic, namely a reduced engine power diagnostic is performed by technicians dispatched by YourMechanic. If you request that diagnostic, the responding certified mechanic will get this issue resolved for you. In your circumstance, the vehicle’s powertrain control module (PCM) has undoubtedly stored one or more diagnostic trouble codes that will identify the "general area" in which the fault lies in the engine management controls. Although the throttle control system is a common trouble area with reduced power, there are quite a few other components and systems that could come into play and, of course, there is always the possibility of multiple, or "coincident", faults. Here are some of the possibilities that YourMechanic dispatched technicians would consider:

Defective throttle position (TP) sensor
Defective oxygen sensor
Defective accelerator pedal position (APP) sensor
Loose or damaged wiring
Defective throttle body
Defective powertrain control module (PCM) (not typical; ONLY if a long, long list of other possibilities is ruled out)
Any fault/error that will affect drivability function
Any fault/error that will affect vehicle performance
A fault/error in the emissions system
A fault/error in the throttle control system
A fault/error in the transmission control system

If you request the recommended diagnostic the mechanic will get this resolved for you. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

ANSWER : Hi there. There are a lot of things that can cause this on your 2012 BMW M5. I usually start by scanning the computer for codes to see what comes up. If there are not codes then I load test the alternator and the battery to see if they are failing. Low voltage in the electrical system will cause this. If that is fine, then it is usually caused by a failing throttle body. I have seen a lot of these fail due to the motors in them hanging up. If the problem is only happening intermittently, this can make the issue hard to duplicate, but you can still have tests done on the car. If you are going to have this fixed, consider YourMechanic, as a certified mechanic can come to your home or office to test the vehicle and diagnose the Engine Malfunction Light.

ANSWER : Hi there. Most of the time, reduced engine power is caused by a restriction of fuel, or the throttle body’s inability to efficiently mix air and fuel. This could be caused by a failing mass air flow sensor, EGR valve or other fuel system components. Since the check engine light is on, you should have a professional mechanic complete an inspection at your location to determine what codes are stored and which components require repair. This should resolve your issue.

ANSWER : It is possible that your vehicle’s PCM has failed. This is somewhat of a common problem amongst many GM vehicles. If the computer has failed, this could be one of the reasons that no trouble codes are appearing and the fact that the problem is intermittent. It is possible that the computer is somehow getting overheated and by stopping the vehicle for a short period of time, the PCM cools down allowing the vehicle to run again. I would recommend having your PCM tested for proper function by a certified technician with experience in computer diagnostics.

ANSWER : It sounds like the vehicle is going into limp mode. This occurs when the powertrain control module (PCM) (also known as the electrical control unit) has determined there is an overboost condition. The computer disables the turbo to prevent damage from occurring. There are many potential causes for an overboost condition, with a failed turbo being just one of them.

Some other possibilities include vacuum leaks, a faulty vane adjustment solenoid, faulty turbo actuator or a bad MAF sensor. There is a technical service bulletin (TSB) # 21-07-65, which advises to check for vacuum leaks before replacing the turbo.

If you would like a second opinion from the dealer, I suggest you give the team at YourMechanic a call to inspect your loss of power condition.

ANSWER : Hello. From what you describe, it would appear that your vehicle may be experiencing some sort of intermittent wiring or sensor issue. If the problem occurred again after driving over a bump, then it may be possible that a damaged or loose wire is shorting or having contact issues. A common issue that can cause stalling is a faulty crank position sensor or wiring. I would carefully examine the engine for any loose or damaged wires. If the Check Engine Light comes back on, I would recommend having the trouble codes scanned before resetting the computer.