pacofortacos
Senior Member
- Joined
- Apr 18, 2017
- Posts
- 3,565
- Reaction score
- 4,343
- Ram Year
- 2016
- Engine
- 5.7
Ported vacuum will have no vacuum to the distributor at idle.
Manifold vacuum will have a lot of vacuum to the distributor at idle.
Just have the truck idling, pull the hose off of the distributor and feel if it has vacuum or not.
If ported, then as you open the throttle, you will get vac. to the distributor and advance the timing.
If manifold, you will be at full advance at idle and lose timing as you open the throttle.
Inside the distributor below the rotor, there is the reluctor and pickup plate - there is a specified gap between them.
Also, at that age, you should check to make sure that there isn't excessive bushing wear in the distributor - there should be almost no side to side play for the shaft that the rotor mounts on.