Engine Compartment

Here’s what you’ll likely find under the hood of a front wheel drive passenger car. As you face the engine compartment, the engine will generally be on the left and the transmission will be on the right. The serpentine belt is on the opposite side of the engine from the transmission, and all power accessories, except the vacuum booster for the brakes, will be located along the route of the serpentine belt: power steering pump, alternator, air pump, air conditioning compressor, water pump. That’s also where you’ll find the idler pulley and tensioner pulley associated with the route of the serpentine belt.

Here’s a look at the main components that will be of interest to you.

  1. Upper front strut mount
  2. Valve cover
  3. Air intake box where the air filter is located
  4. Fuse box
  5. Battery
  6. Vacuum booster for power brakes
  7. Radiator
  8. Air duct intake just above the throttle. The throttle is operated by a cable connected to the gas pedal. This is the intake side of the engine and that’s where fuel injectors will be located.
  9. Oil filler cap
  10. PCV valve
  11. Engine control module
  12. Brake fluid reservoir. Immediately beneath the reservoir is the master cylinder that connects to the vacuum booster mounted on the firewall. The master cylinder and vacuum booster are always mounted directly in front of the driver because that allows for convenient connection of the brake pedal linkage.
  13. Coolant reservoir
  14. Windshield washer fluid reservoir
  15. Air conditioning compressor. In this case, the water pump is mounted below this compressor and towards the firewall a bit, as it uses power from the serpentine belt to operate.
  16. Power steering fluid reservoir. Immediately below the reservoir is the power steering pump, and below that is the serpentine belt tensioner. In this particular case, the alternator is located beneath the serpentine belt tensioner, as it gets power from the serpentine belt as well.
  17. Exhaust manifold coming off the engine
  18. Engine oil dipstick (yellow handle)
  19. Transmission dipstick (red handle). If you’re looking for the transmission, just follow the dipstick tube. In this particular vehicle there is a spin-on transmission fluid filter (not shown) that looks very much like the oil filter (not shown) associated with the engine.
  20. Timing chain cover (as part of the valve cover). Below this portion of the valve cover is a plate that seals in the timing chain. On this plate there is mounted an idler pulley that helps route the serpentine belt among the various powered components.
  21. Upper motor mount
  22. Serpentine belt
  23. Main radiator hose
  24. Air intake ducting
  25. Firewall
  26. Wheel well
  27. Spark plug wires
  28. Engine compartment frame member