Skip the auto shop - Our mechanics make house calls

Q: The car stalls occasionally as if the fuel is not been pumped

asked by on

My vehicle occasionally stalls as if I've run out of fuel. My mechanic has change fuel pump twice as well as the fuel filter. Again as soon as the air condition is put on, the car becomes so heavy for want of better word that it doesn't pull as it should.

My car has 252333 miles.
My car has a manual transmission.

It sounds like you may have a fuel supply issue that corresponds to the load put on the motor when you turn the A/C on. This may be related to a faulty MAP sensor. The Manifold Absolute Pressure (MAP) sensor senses engine load and generates a signal that is proportional to the amount of vacuum in the intake manifold. The engine computer then uses this information to adjust ignition timing and fuel enrichment. When the engine is working hard, intake vacuum drops as the throttle opens wide. The engine takes in more air, which requires more fuel to keep the air/fuel ratio in balance. When the computer reads a heavy load signal from the MAP sensor, it adjusts the fuel mixture to slightly more rich than normal so the engine can produce more power. The computer will then retard (back off) ignition timing slightly to prevent detonation that can damage the engine and decrease performance. This may also be caused by other closely related components such as a dirty or failing mass air-flow sensor, a faulty throttle position sensor or potentially a vacuum leak. I would recommend having an expert from YourMechanic come to your location to diagnose and inspect your vehicle.

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: Stalling issues, error codes

Hello. The P0442 error code is an evaporative emission control code and is an indication of a small leak being detected in the evaporative emission system. There are usually no visible symptoms of this error code, other than the check...

Q: Engine not running correctly after rebuild

I'd need to know the symptoms you are having but I'm assuming the engine is burning oil. Valve seals control the oil that lubricates the valve stems and prevents it from seeping into the guides in excessive amounts. The piston...

Q: my engine is louder than usual it seemed to be overworking today it was vibrating then while driving I smelled strong burnt like s

Hello, thank you for writing in. The vibration is coming from the engine not working correctly. The cause of this is the focus of our attention. The white smoke is a sign that a fluid of some sort is being...

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...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...
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.