Q: Underpowered and shaking under load

asked by on

My car, when under load is shaking and not performing well. I thought it might be a bad spark plug, so I got new plugs, then I thought it could be a plug wire, so I tried that, and that wasn't it. Last I tried replacing the wire to the distributor, but to no avail. I have no idea what to do now, so please help me.

My car has 248344 miles.
My car has a manual transmission.

Hi there. This may suggest a fuel delivery problem such as bad or dirty fuel injectors or potentially a faulty O2 sensor. As you may know, the oxygen sensors which are part of your emissions system read exhaust gases to determine whether or not the appropriate amount of oxygen is present in the exhaust. Based upon this reading, this information is relayed to the car’s ECU which then makes a determination as to whether or not to add more or less fuel to the engine. When too much or too little oxygen is present, this will cause Check Engine Light to come on.

Too much oxygen may be present in the exhaust gas due to things like an exhaust leak, a vacuum leak, a faulty mass air flow sensor (causing a lean fuel condition) or faulty fuel injectors.

Too little oxygen may be present in the exhaust gas may be caused by things like a clogged air filter, a failing mass air flow sensor (causing too much fuel to be introduced to the motor), bad fuel injectors or a clogged catalytic converter. When the O2 sensor is not working properly, this will cause false readings to be relayed to the computer causing inaccurate adjustments to be made to the intake and fuel system in your engine. I would suggest having an expert from YourMechanic come to your home to inspect the loss of power and pinpoint the proper repair.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. Underpowered and shaking under load

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: What is making my front end vibrate?

I would first test the motor or transmission mounts. If it is not the motor mounts, the vibration might be arising as engine load and speed "interact" with the gearing at that particular speed causing a dynamic balance issue. The...

Q: Noise after the car is turned off, car idles rough - 1973 Nissan 240Z

Hello. It sounds like the starter relay might be bad and is causing the starter to stay on, which is the clicking noise that you are hearing. There could also be a problem with the starter solenoid. The problem you...

Q: My BMW steering wheel shakes when driving 50 to 60 miles an hour

Hello there. Many faults will cause your 2002 BMW X5 steering wheel to shake when driving at speed. The most common faults are the wheel bearings, tires out of balance, bent wheel, driveshaft balance, or the struts. If the vibration...

Related articles

What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
What are the Car Pool Rules in Hawaii?
Hawaii is widely regarded as a land of vacation and relaxation, and as such, its scenic roads and routes are far better known than the state’s freeways. But, as with all...
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.