Here's a breakdown of why you might be having trouble finding it and how to locate it:
* Obstructed View: Vacuum lines, wiring harnesses, and the air cleaner assembly can significantly obscure the distributor. Try carefully moving these components aside to get a better view. Take photos before you move anything to aid in reassembly.
* Difficult Access: The location can be cramped, making it hard to reach with a wrench or socket. You might need a swivel socket extension or a flexible ratchet to get the right angle.
* Hidden Under a Bracket: Sometimes a small bracket or part of the intake manifold might partially hide the bolt.
* Incorrect Identification: Ensure you are looking at the *distributor* and not a similar-looking component.
* Unusual Modification: Someone might have modified the engine, altering the distributor's mounting.
How to find it:
1. Clean the Area: Thoroughly clean the area around the distributor. Use a wire brush, degreaser, and compressed air to remove dirt and grime that could be obscuring the bolt.
2. Visual Inspection: Carefully inspect the entire base of the distributor. Look for a bolt that appears to secure the distributor to the engine block. It will likely be a relatively small bolt (8mm-10mm is a common size).
3. Feel Around: Carefully run your fingers around the base of the distributor. You might be able to feel the bolt head even if you can't see it clearly.
4. Consult a Repair Manual: A repair manual specific to your 1983 Dodge D150 with a 318 engine will have diagrams and detailed descriptions of the distributor and its mounting. This is invaluable.
5. Online Resources: Search online for "1983 Dodge D150 318 distributor bolt location" or similar. You might find pictures or videos that show the bolt's location.
Regarding the Electronic Fuel Injection (EFI) on the air cleaner: That's likely a part of the air flow sensor or another EFI component. It's unlikely to have anything directly to do with the distributor hold-down bolt. However, it could be obscuring your view. Carefully inspect it to make sure it's not in the way of the distributor bolt.
If you've tried all of this and still can't find it, consider seeking help from a mechanic. They'll have the experience and tools to quickly locate the bolt.
