* Fuel Delivery Problem:
* Clogged fuel filter: A dirty fuel filter restricts fuel flow, especially under high demand. This is a relatively inexpensive and easy fix.
* Fuel pump failing: A weak fuel pump might not be able to keep up with the increased demand during acceleration. This is a more serious problem requiring replacement.
* Fuel pressure regulator malfunction: This regulates fuel pressure; a faulty one can cause inconsistent fuel delivery.
* Air Intake Issue:
* Mass airflow sensor (MAF) problem: The MAF sensor measures the amount of air entering the engine. A faulty sensor provides incorrect information to the computer, leading to poor fuel mixture and stalling.
* Dirty air filter: A clogged air filter restricts airflow, similar to a clogged fuel filter.
* Vacuum leak: A leak in the intake system can cause a lean fuel mixture and stalling.
* Ignition System Issues:
* Spark plug wires: Worn or damaged spark plug wires can cause misfires, leading to poor engine performance and stalling.
* Spark plugs: Worn or fouled spark plugs will also cause misfires.
* Ignition coil: A failing ignition coil can't provide sufficient spark to all cylinders.
* Transmission Problems (Less Likely, but Possible): While less probable, a transmission issue could contribute if the stall is accompanied by other symptoms like slipping or harsh shifting.
What you should NOT do: Continue driving the car regularly with this issue. This could cause further damage to the engine or lead to a dangerous situation.
What you SHOULD do:
1. Check your fluids: Make sure your engine oil, coolant, and transmission fluid (if automatic) are at the correct levels.
2. Get it checked by a mechanic ASAP: This is not a problem you can safely diagnose or fix yourself unless you have extensive automotive experience. A mechanic can properly diagnose the root cause and perform the necessary repairs.
3. Mention the exact circumstances: When you take it to the mechanic, clearly explain that the stalling only happens under load, specifically when passing another vehicle. This crucial information will help them focus their diagnostics.
Ignoring this could lead to serious engine damage, and it's a safety hazard. Don't delay getting it checked out.
