Skip the auto shop - Our mechanics make house calls

Q: My 1993 GMC Sierra will barely go past 40mph

asked by on

Hey, i have a 1993 gmc sierra with 256k on it right now. And it will act like it will barley wanna go past 40 mph and when it does you cant hold a speed at all without the rpms going to 2,000 and sometimes 2,500

My car has 256000 miles.
My car has an automatic transmission.

This may be a sign of a dirty or failing mass air flow sensor. The mass air flow sensor is a unit in the intake system that monitors air intake as it is mixed with fuel prior to being injected into the motor. When this fails, this 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 is what causes the hesitation or loss of power you describe. This can also cause the engine to struggle to idle for the same reason. I would suggest having a professional from YourMechanic come to your home to diagnose your mass air flow sensor.

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

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: Ac system

The low vacuum is an indication that there is a leak somewhere in the A/C system, gauges or vacuum pump. I suggest getting this looked at by a certified technician, like one from YourMechanic, who will be able to perform...

Q: Car is losing power after driving a few miles. Any suggestions as to what could be causing this?

Hi there. There are typically two systems that cause an engine to loose power - ignition and fuel. The first step would be to have a professional mechanic download any stored error codes from the ECU on your '96 Cadillac....

Q: Wheel locked

Try turning the wheel back and forth while turning the key, use caution not to break the key. If you still cannot get the key to turn, you may have to have the ignition lock cylinder replaced. A certified technician,...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...
How Much Does a Mechanic Make in Vermont?
Automotive technician jobs in Vermont have an average mechanic salary of $37k, with some mechanics earning a salary of $53k.