Generally it would be an unmetered air leak in the intake system. Or it could be a faulty crank/cam sensor
when the engine weres down
What causes a 1998 Pontiac transport to run hot and engine shuts off
A bog down in a 1986 Toyota pickup with a 22R engine can be caused by several issues, including a clogged fuel filter, malfunctioning carburetor, or ignition system problems such as faulty spark plugs or wires. Additionally, air intake restrictions or vacuum leaks can hinder engine performance. Regular maintenance and inspection of these components can help identify and resolve the issue.
open the hood, look down between the rad. and the engine. There it is.
Becuase you're revving the engine. Becuase you're revving the engine.
Either a faulty engine temperature sensor or the wiring to it.
The most common cause of engine surging (rev up and down) is a dirty air filter.
The engine is not running!
Revving up and down is usually a symptom of a dirty air filter.
spark pluggs
Flushing sludge from your engine is not a very smart thing to do. Almost every automotive technician will agree with that. Flushing out an engine causes all the sludge to drain down into the oil pan. Which in turn tends to plug up the oil pick up and causes engine damage.
The governor spring adjustments