Toyota Repair: 84 pick-up stalling when idleing, gasket leaks, intake manifold gasket

Question
wonder if I might get some help with this problem?
My 84 Toyota truck is stalling when it idles, it warms up okay, drives fine,
but will not idle correctly.  I've noticed no hesitation beyond normal, very
little if any loss in mpg, and no other signs I might associate with this
problem.  It is an old truck and has better than 233k miles on it.  (It's got
that old 22-R engine in it, if that is of any help)

I've tried some of the basics, I've replaced the fuel filter, adjusted the
idle speed and mixture and used carb cleaner on the carb.  Unfortunately my
knowledge is limited when it comes to the carb.  I've also tried fuel cleaner
(additive) and have been putting in higher octane to see if that is of any
help.  So far no luck on any of this.

Any ideas?

Thank you,


Answer
These engines had a lot of problems with intake manifold gasket leaks especially near the number four cylinder, try spraying some kind of carb cleaner around the rear where the egr valve connects and see if the engine speeds up, if so there is a leak and the intake manifold gasket requires replacement.