These were good trucks. I bought a brand new 1986
model. This vehicle may or may not be computer
controlled. To find out see if it has a "Choke" light
instead of a check engine light. If it does, the vehicle
is not computer controlled and will be easier for you
to work on and get parts for. My first suspect would
be the electric choke. They always burned out and
that would keep the choke plate closed. As the
engine warms up the choke plate, on top of the
carburetor, should gradually open. If not, use a
screwdriver and hold it open. If the engine runs
good when you do that, the choke is burned out.
Another thing to look for is the exhaust manifold
heat riser valve not opening, if equipped. It will be
on the passenger's side exhaust manifold right
where the manifold bolts to the exhaust pipe. With
the engine cold you should be able to move the
valve by hand. If not, it's stuck and needs to be
replaced. A clogged catalytic converter will make
the engine run poorly as will clogged or misrouted
PCV system hoses. If you determine the carburetor
is the problem, DO NOT replace it with one from the
auto parts store!! DO have the original carburetor
rebuilt, complete with a new electric choke. I
learned that lesson the hard way with my 1970
Pontiac Catalina!! Hope that helps! Jim
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