Here are some possible causes:
* Fuel Leak: This is the most serious possibility. The leak could be from:
* Fuel injectors: A faulty injector seal or a cracked injector body can leak fuel.
* Fuel lines: Cracks, corrosion, or loose connections in the fuel lines can cause leaks.
* Fuel pump: A failing fuel pump seal can leak fuel.
* Fuel filter: A cracked or damaged fuel filter can leak.
* Fuel pressure regulator: A malfunctioning regulator can leak fuel.
* Evaporative Emission System (EVAP) Leak: This system prevents fuel vapors from escaping into the atmosphere. A leak in any part of the EVAP system (hoses, canister, purge valve, etc.) can allow fuel vapors to escape and be detected as a gas smell.
* Loose Gas Cap: While seemingly minor, a loose or improperly sealed gas cap can allow fuel vapors to escape and contribute to a gas smell, especially after refueling.
* Carburetor (if applicable): Older GMC Jimmys might have carburetors. Leaks in the carburetor or its associated components can lead to a gas smell.
* Fuel spillage: Accidental spillage during refueling or maintenance could also cause a lingering smell.
What to do:
1. Safety First: Do not start the engine. Park the vehicle in a well-ventilated area and turn off the ignition.
2. Identify the Source: Carefully inspect the engine compartment for any signs of fuel leaks – wet spots, puddles, or dripping fuel. Look closely at fuel lines, injectors, and the fuel pump.
3. Check the Gas Cap: Make sure your gas cap is securely tightened.
4. Professional Help: If you cannot locate the source of the smell, or if you see any signs of a leak, take your GMC Jimmy to a qualified mechanic immediately. A fuel leak is a serious safety hazard and needs professional attention. Ignoring it could lead to a fire.
Do not attempt to diagnose or repair the problem yourself unless you have significant mechanical experience and the proper safety equipment. Fuel is dangerous, and improper handling can lead to injury or fire.
