Skip the auto shop - Our mechanics make house calls

Q: Engine RPMs drop suddenly from 2500 to 500-1500 RPM on 2013 BMW 650i

asked by on

Under moderate to heavy acceleration, my car will lose power. If accelerating anywhere over 2500 rpm, after accelerating the engine rpm suddenly drops by 500-1500 rpm. Then it continues to accelerate from the lower rpm. It happens only once each time I press on the gas pedal. There are not any codes that appear. The dealership has examined the problem and they have not been able to find the cause. They ran fuel pressure tests, vacuum leakage tests, and might have checked the throttle position sensor. Can you tell me what is causing this and how to solve the problem?

A: Thanks for writing in about your 2013 BMW 6...

Thanks for writing in about your 2013 BMW 650i. The symptoms sound similar to a vehicle with a throttle position input error or a major boost leak in a forced induction vehicle. To verify this, I would recommend having a professional, such as one from YourMechanic, diagnose the loss of power problem in order to have this repaired properly.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Got a tune up. Sputtering during acceleration abd now it won't start. Smell of gas without touching pedal. No interior lights and battery is good

Hello and thank you for your question. Sounds like a couple things are wrong with your car. First there is a crossed wire with the spark plug wires. If only two wires are crossed, then the vehicle will run on...

Q: Sudden jerk upon acceleration, low gas mileage - 2013 Range Rover

Hey there, thanks for writing in about your 2013 Range Rover. You may have a problem with the throttle control that may be dangerous to drive. There are many other possibilities, such as a vacuum leak, faulty mass air flow...

Q: Car shut off during driving

Hello. It sounds like your 2002 Porsche Boxster lost all battery power. This occurs when the alternator fails and causes the battery to die. It is a common issue. The battery must first be checked and then replaced or recharged....

Related articles

How Long Does a Distributor O Ring Last?
The distributor is part of the ignition system in your vehicle and its purpose is to route high voltage from the ignition coil to the spark plug. The spark plug then...
How Long Does a Heater Control Valve Last?
Keeping the right amount of coolant in a car is essential in keeping the engine at the right temperature. Failing to have the right amount of coolant or even bad elements...
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.